Grumblewartz wrote:
OK, here it goes...

General:
Two CAD's is quite effective. It allows you to take more heavy support, which is an incredibly crowded slot.
I run a mek horde, tons of walkers and light vehicles, so I use the Ghaz supplement for the 4++ kustom force field, that's about it. I can't give any other advice.

HQ:
Warboss with mega armor and a lucky stick is popular. Great for adding protection to a unit by soaking up ap 3 or worse. Ap 2 you just look out sir to someone else
I use the mek on a bike all the time. But, it depends what you need it for. I use it to keep up with my kans/deff dreads/other vehicles.

Troops:
Most people lean towards choppas, just because they are cheaper and the extra attacks don't hurt. Shootas are pretty great themselves and can do some damage, but, in doing so, can put themselves out of charge rage, which is usually where Orks wanna be.

Elites:
Nob bikers are too pricey. Regular bikers are vastly superior.
Meganobz are most certainly worth their points. 3 in a trukk offers a dangerous, but cheap and disposable threat
Tanbustas are king - burnas are too pricey and susceptible to damage. Kommandos are hit or miss - again, they suffer from poor survivability

Fast attack:
Dakkajets are still quite solid. Deffkoptas in singles are good to grab objectives and add to the general target saturation if you have the free slots. A few in a squad is still fairly effective though.
Stormboyz are also hit or miss. They are relatively cheap, but their inability to take heavy armor really hurts.
Warbikes are fantastic. Squad size - go big, usually, unless you are trying to swarm the opponent with MSU.
Outflanking buggies are a economical distraction unit that can quite seriously threaten backfield artillery, the rear armor of tanks, etc. Often all you need to do is stun the enemy tanks to give your boyz time to advance, so the ap 3 isn't a big deal.

Heavy support:
A ram is fine on the battlewagon, but most people don't invest too heavily in them. They are already fairly expensive. If you do get the killkannon, do not bother with other upgrades.
Looted wagons lack defense to a serious degree. If you are playing friendly games, they can be fun. Against more competitive lists, they die too easily.
Flash gitz in a battlewagon can do some serious damage. Beware of enemy flamers though!
The general consensus is that the Gork and Mork...anauts... are too pricey. But, my Morkanaut almost always pays for itself. The kustom force field on such a large base helps keep the kans and dreads advancing. Beware though, it can be blown up with a single ap 2 shot.
Kans are too pricey and weak. However, in a kan/dread/naut list, they are useful. This is, again, only if you aren't playing in a very competitive environment.
Mek guns are fantastic and being Orks, super easy to convert out of almost anything. Your imagination is the ceiling.
Lootas are an all around safe, solid choice. Put them in cover - or better yet, a building - and they will do some work.

As effigies of Gork or possibly Mork, you can't go wrong with Stompas!