In 2 vs. 2 this is even more apparent as suddenly you are an 'army of one.' The multiplayer maps are also quite compact (the biggest I've seen being the Mausoleum) which means that you're never far away from the action, and this helps to move the game along at a frantic pace.
In terms of suspense, I can assure you that there is no worse sound than hearing a chainsaw revving up right next to you and suddenly finding yourself on the wrong end of a grisly death. Needless to say that chainsaw can be periodically revved to scare the opposition. As you can fire blindly into areas, I heard machine gun fire on a number of occasions and frantically looked around, expecting to be shot at any moment. It all builds the suspense.
I think the best thing about the multiplayer for me is the balance. No one side is given preference over weapons (any pick-up weapons are placed in the middle of the map and it becomes a race to get them). This then of course opens up the possibility of being killed right at the start of the round as you rush for the best weapons. So your tactics have to be spot on.
So to sum up, if you own a 360 and don't have Gears then buy it! If you don't own a 360 then buy one and buy Gears. If you own a PS3 then sell it on eBay and buy a 360 and Gears. And if you do have Gears, then savour the fun as it may be another whole generation before there is a title to top it.