Hey guys. I assume not many of You are as crazy about Imperial Fists as to purchase the supplement at midnight
So in case anyone wonders what new things they can read about in the fluff section - I got some bits for You.
I have finished reading only now (was a busy day) so here's a full update, I had to change some info given previously as it turned out incomplete

Enjoy!
First of all. Some bad news:
https://twitter.com/HerrDexter/status/393986559487139840/photo/1
No rules will be discussed here, just fluff. You can check new rules here:
http://apocalypse40k.blogspot.com/2013/10/sentinels-of-terra.html (poorly written but I can confirm rules posted there)
Big new fluff changes for Imperial Fists Chapter:
1) Chapter Master
Vladimir Pugh, who has been a figure since Index Astartes vol.II
dies a glorious death while fighting the Tyranids
2) Though all eyes are on 1st Company Captain Darnath Lysander - he refuses to take Chapter Master's mantle as he now understands he wouldn't be a good leader as long as his Iron Warriors arch-nemesis draws breath
3) New hero on the stage, 5th Company Captain
Vorn Haggan is appointed the new Chapter Master and his cool head drives the chapter to new glory without needles stubbornness against all odds
4) Another new hero, sgt. Tor Garadon becomes a key figure for 3rd Company and eventually it's Captain
What's good in this supplement?
1) Fluff actually progresses since last time

In the past we saw sgt.Lysander (3rd edition) elevated to position of captain (4th edition) - now we see old Chapter Master dead and succeeded by new hero - Vorn Hagan
2) the 80+ pages are a great read, written with more wit and flow than
SM:Codex itself, I enjoyed it as I would a good short story
3) Many important figures in the chapter are given names, so a cannon is set and we can disregard some tidbits from books noone really liked
4) We see rise, darkest hour and retribution of 1st Company Captain Lysander - he evolves during the story and is a very defined character with lots f new fluff added
5) 3rd Company gets lots of spotlight including it's full roster with names during their glorious Crusade of Thunder
6) 5th Company is shown as a very important company present at key moments in chapter's history. It's also the company new Chapter Master originates from
7) 2nd, 7th and 9th Companies are mentioned with a chunk of fluff for each. Their captains are described.
8) as always, with these supplements - Altar of War missions allow IF player to test oneself in conditions Imperial Fists find themselves ever so often (outnumbered, bloody but unbowed)
9) 5 Historical Missions neatly recreate major events in chapter's history including Fall of Malodrax (Iron Warriors base), glorious death of Vladimir Pugh inside Space Hulk infested by Tyranids etc...
It's a great read for any Iron Fists player and SM fan in general. Successor chapters like Crimson Fists have no mention here and won't find this useful. Rules are ment for 3rd Company so I can see lists composed of 2 companies allied, one using rules from Codex:SM and the other from this supplement. Only thing I really regret is that no full current lineup of ALL Captains and Company Names is found in the volume...
New names / confirmed positions in Imperial Fists fluff:
- 1st Company Darnath Lysander
- 2nd Company Captain Helion
- 3rd Company "Sentinels of Terra" Captain Julius Vogen, later succeded by
Captain Tor Garadon and again by Captian Alaric Eshara only for Tor Garadon to return as it's captain in the end.
- 5th Company Captain
Vorn Hagan who later becomes new Imperial Fists Chapter Master (his successor in 5th company is sadly not mentioned, so we're back to Captain Khusaor from "Sons of Dorn" novel)
- 7th Company Captain Jonas
- 9th Company Captain Terell (laster steps down as he lost eyesight due to Tyranid acid)
- 10th Company Captain Monteith
- Brother Micoleth Karazan, Techmarine attached to 3rd Company
- Epistolary Xeros Darsway, Librarian attached to 3rd Company
- Chaplain Ivor Markov of the 3rd Company (later inhered in Chaplain Dreadnaught sarcophagus)
- Brother Conarth, Dreadnaught of the 3rd Company
- Brother Makan, once a Scout Sergeant and mentor to Lysander, now a Venerable Dreadnaught attached to 3rd Company during Crusade of Thunder
- Chief Librarian Haldor Marzon
Tor Garadon's military career:
- recruited from political family, never had any interest in politics
- sergeant in 3rd company, proves a great leader after it's captain is killed
- is Acting Captain during Crusade of Thunder and trail of Lysander
- he eventually obtains the 3rd Company Captain
- many years later he's promoted to the Captain of 2nd Company
- after 3rd gets nigh annihilated and it's new captain killed, he returns as Captain and with advices from Lysander rebuilds his old company once again
Darnath Lysander's military career:
- pilgrim on Terra as a child, devout believer
- is recruited by old Imperial Fists chaplain
- learns that Emperor was a man not god and gains insight that most mortals don't have
- learns alternative Bolter Drill from Scout sgt. Makan, hones it and makes it his own trademark
- as a Sergeant of the 2nd Company he openly opposes Index Astartes bolter drill he deems inferior to his own
- this almos costs him degradation and punishment, but his own Bolter Drill saves the day and gets recognition
- he becomes Captain of the 2nd Company
- eventually he takes lead in 1st Veteran Company
- events of "lost in warp" and "prisoner of Iron Warriors" take place (we all know that, it's old fluff)
- he is later reinstated as Captain of the 1st, leads assault on Taladorn
- his stubbornness and refusal of help cost 3rd Company many lives
- he is demoted and takes charge of 3rd Company in order to rebuild it and train new recruits
- after Crusade of Thunder's initial stages he returns to lead 1st Company
- he remains at this position in all following key events, refusing the promotion to Chapter MAster
Vorn Hagan military career:
- Captain of the 5th Company in many key events
- fights along Lysander against Iron Warriors Warsmith Shon'to on Taladorn
- is one of few to oppose Lysander's recklessness during Darnath's trail and demotion
- fights side by side with Chapter Master Vladimir Pugh during desperate battle in the heart of infested Space Hulk on Drashin's orbit
- after Pugh's death and annihilation of Tyranids on Drashin he is appointed the new Chapter Master
- in his cool judgement he moves entire Phalanx (Imperial Fists massive space station) into Malodrax orbit and commands the chapter in their glorious battle against the Iron Warriors
- according to calendarium he remains Imperial Fists Chapter Master to this day!
Battle of Taladorn:
- Lysander is shown as stubborn donkey-cave, refusing help from Ultrasmurfs and Period Angels
- 5th Company along with it's captain survive against all odd and with their asses covered by 3rd Company
- 3rd Company however takes a big hit, their captain gets killed, vet. sgt. Garadon takes charge
- Since Lysander refused help and was obsessed with killing all Iron Warriors with use of Imperial Fists only, 3rd Company gets raped by daemon engines
- Ultramarines' cpt. Sicarious and Blood Angels' cpt. Tycho offer help again, and Tor Garadon accepts it (asking them to focus on his homer beacon) much to Lysander's disaproval
- Smurfs and Emos save the day turning what was supposed a glorious battle into a play of Loyalists performing search-and-rape on Iron Warriors
Aftermatch (with a plot seen in many USA action movies):
- Lysander behaves like a spoiled girl and leaves Terminator sergeant Julan to thank Sicarious and Tycho
- roughly 90 Imperial Fists were killed in battle, including Captain of the 3rd
- after recovering from his injuries, Tor Garadon, now acting commander of the 3rd goes straight to Chapter Master Pugh and openly blames the horrible blow that 3rd company took on Lysander's recklessness
- Vladimir Pugh assembles a trial where all captains are present and with Garadon acting in 3rd's place (with no right to vote however)
- hearing the accusations, Vorn Hagan (captain, 5th Company) is furious as he realizes it could have been his company getting killed, he's very upset by Lysander's actions as he saw him a personal hero
- finally Lysander gives his testimony which is stubborn and can be summarized as "Dude, it's like our style to get killed over such things - dat is the glory, man!"
- Half the captains applaud, others facepalm - Pugh is in a pickle as he cannot openly demote or punsih Lysander
- And so smart Vlad devises a cunning plan - he temporarily moves Lysander to the position of 3rd Company Captain saying this isn't demote but a penance and chance to rebuild the company as Lysander is know for his drill skills (da-da-da-dam!)
- Tora Garadon is obviously angry as he hoped he will become Captain, Lysander rubs his hands though
- and here comes a typical USA movie twist - Lysander gets a ban on "Iron Warrior smashing" he loved so much
- 3rd comapny gets assigned to Crusade of Thunder and their new enemy is stinky Orks. Lysander is angry with Pugh, his new sergeant is angry with him, overall dead silence commences
3rd Company rebuild and ready for Crusade of Thunder:
- Captain Darnath Lysander, Honor Guard of Terminators, Land Rider Crusader "Legend of Roma"
- Chaplain Ivor Markov
- Some survirors of 3rd company's actions on Taladorn are promoted to Sergeants
- Tor Garadon is now Sergeant Primus (of 1st
Tac Squad) and has distinctive, black helm with white stripe "marking him as veteran" (who came up with this marking all
fo a sudden?!)
- 1st company's veteran sgt. Odin also becomes sgt. in 3rd
- about 40 tacticals are drafted from Captian Jonas' 7th Company to replenish those lost on Taladorn
- some scouts from Captain Monteith's 10th Company are lifted to Space Marine status and also joined into 3rd's new ranks
- overall squads are mixed so that no squad would be totally veteran or entirely rookie
- 2 Dreadnaughts : Brother Conrath (who had some spotlight on Taladorn) and newly assigned Venerable Dreadnaught Makan (Lysander's old mentor)
- during 15day voyage to Magor Rift (where crusade would take place) Lysander trained his new comrades in his unorthodox Bolter Drill
- Garadon and Lysander poorly hide their disgust for one another but show respect in professional way
Stay tuned for more