I actually think this game may turn out better than L4D with vanilla settings for versus. Survivor play looks to be a LOT harder, especially with the events that force you to run from point A to point B. Throw in a charger or smoker in there to cause some separation, and a hunter/jockey/spitter/boomer on the rest to slow down the rescue and you likely have at least one incap.
I also thought that the addition of the new SI may mean the end of the quadcap, but I think they just may be a little more "exciting" than in L4D. I doubt the standard L4D 3-1 quadcaps is going to be possiblee. But why not a smoker/hunter/jockey/charger combo? I don't think the jockey directly damages the survivor, but they do prevent them from meleeing and shooting, and once a natural horde comes (or one of the other SI kills the survivor and is free) the last survivor will get incapped. (EDIT: Apparently the jockey does do a small amount of damage). This of course depends on how the selection of SI to spawn is chosen. In L4D we have a general idea that (if no one spawns in), whoever dies last will become a hunter, so a hunter last is a standard setup, smoker last is a boomer 3-1 and boomer last is smoker 3-1. But even that we arent 100% sure on as there seems to be other factors involved, but in L4D2 with so many different SI, it will be much harder to predict what you will get, or control it by dying in the right order. I'm guessing that you wont have a smoker and a charger at the same time since they are both designed to split the survivors up, It is also possible that smoker/spitter wont be allowed together because they both have long range attacks. Similar with the boomer/spitter, both are projectile style attacks.
I do see some new interesting tactics for survivor already forming. Boomer bile will be a great way to slow down the tank since he will be surrounded by the horde. The adrenaline needles seem interesting. A great way to push that extra little bit to spawn a tank or start an event while the SI are down, but besides that, it will likely just lead to more separation of the survivors.
I understand the anti-shiva stacking, but I think it would make more sense if the survivors were a little more "solid" since right now you barely push back against people. And this doesn't prevent corner camping, as in most places the survivors can easily have 3 crouched infront, with one guy watching over their heads.
The only thing that really worries me is the defibs. L4D was extremely unbalanced with kits because you do so much work to get someone black and white, and then 6s later they are back to full health. But imagine you are able to get someone black and white, and then kill them before they can heal, or you are able to get someone killed in very well planed and executed attack. Someone pulls out their defib, zap, all that works is gone and all it counts for is an incap (and could possibly even reset the bw count to 1 incap, so they wouldn't even require a heal).
The new set of weapons that are more like T1.5s are a great addition. Hopefully a lot of levels wont have T2 spawns, and the ones that do wont be a cakewalk like NM4/DA4/BH2/etc.
New shotty: I like the slower rate of fire as it leads to easier infected play.
New assault: Hate it from a survivor standpoint because of the burst fire, but its good for infected because it forces the survivors to play smarter with it.
AK47: Seems like a solid weapon, not quite as accurate as the old assault, and the smaller clip size hurts a little.
New sniper: hunting rifle > this crap. The larger clip is nice, but it doesn't seem to shoot much faster, and the hunting rifle can one-shot any of the standard SI (minus the charger, witch and tank).
Melee weapons are cool and its great that they do FF so you can just all grab a frying pan and bash your way through every level and every horde. You could potentially have 3 people with them for corner camping, and all crouch in front while continuously swinging, and then have one guy standing with one of the various shottys clearing out the rest of the infected but that means you only have a single set of double pistols which makes the tank a ton harder when you only have T1s.
New pistol looks cool, but I don't think it will get much use because of its slow rate of fire and small clip. It will have to do a lot of damage to be able to compete with a set of double pistols for DPS. It will probably have a better damage falloff though, so it will be better for longer range.
Wandering witch is a whole new threat, but only when you have T1s. With even the T1.5 shotty you can easily mow her down, and even run right up to her and get an easy crown.
But after all this talking, we wont really know how VS gameplay is until we try VS. Valve was smart enough to fix the bug in the old L4D demo that allowed someone to host locally, force versus and then try out the SI (not actually in-game, but just try playing as them since the director wont spawn human SI) (EDIT: See above in my post to play as the SI). And of course the new scoring system (such as SI getting 10 points for every incap) will have a huge impact on gameplay and probably starts as well.
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