I saw some time back a bit of talk-talk about how 8e was going to adjust the balance of shooting and assault.
I've decided to process some numbers.
Our hypothetical Meltagun team is not feeling particularly good about it's prospects for 8e.
An Imperial Guard Lascannon section doesn't fare much better, but at least it wasn't that good at tank killing in the first place.
We haven't seen the stats on monstrous creatures, to see how many wounds they have, but we can be fairly certain that a Carnifex is going to have more than 4 wounds if a Space Marine Captain has 6. In addition, T6 Monstrous creatures are more resilient against high strength weapons than
Small arms also either became weaker or remained the same:
If the weapon currently ignores the target's armoursave, or was 2 or more points higher in strength than the target's toughness, it became marginally worse. Otherwise, it remains at the same effectiveness. With new marines, and many other units, having an increased number of wounds though, you're still getting less out of your bolters in 8e than you are in 7e.
We can fairly confidently say that the lethality of shooting will decrease rather drastically.
So, the question is, how does close quarters combat fare?
Well, against tanks, our team of Terminators is going from "tank is a write-off" to "can't kill the tank". Fairly drastic. At least we know the gun on that tank is now a piece of crap, if it's any consolation to the terminators.
On the small arms scale, your chainsword is now equivalent to your bolter, and is exactly as effective as it was in 7e, against both Guardsmen and Space Marines.
Losing the bonus attack for charging hurts assault quite a bit.
There is one more thing to keep in mind, and that's the fact that you can now assault on the turn you disembark. However, you have to debark before the transport tank moves in the turn. According to
GW, they "debark, then move, then charge". We're lacking the distance the models can be placed from the hatches during the debarkation action, and the movement speed of any common transport, but I can speculate that it will probably be quite possible to make turn 2 charges across the board fairly reliably, which is a fairly significant improvement as well, giving more survivability to assault units on their way into the fight.
However, units wounded in the assault phase, while prevented from shooting, can voluntarily leave combat, allowing other units to shoot units otherwise in combat. I'm going to guess that this won't have too much of an effect, as dedicated heavy assault units tend to be able to wipe out their targets as is, but it does mean that CQC is less "safe".
As a whole, things in general look like they're going to be at least as durable, if not drastically moreso in the case of armor. I think assault may also be more viable, thanks to taking drastically less fire on the way into battle.
Member of 
DKoK Blog:
Have a look, I guarantee you will not see greyer armies, EVER! Now with at least 4 shades of grey
