That version was the PS3's. Making its playable debut at the show, the PS3 edition was there to show off the game's co-op mode, which takes the form of a disjointed series of missions built loosely around the timing and events of the singleplayer campaign.
Aside from a recent Bad Company "experiment" (DICE's words, not mine), it's the first time the developers have taken a co-op mode seriously in its games, and...it shows.
There's nothing wrong with it, of course. But there was nothing particularly interesting about it, either. Battlefield is a series famous for its expansive multiplayer maps. It's now also trying a more involving, heavily scripted singleplayer campaign. The co-op level I played felt like a third wheel.
Beginning with a stealthy section through a building in an Iranian street, in which the two players could occassionally split up and perform simultaneous kills, the action moved out into a street with a series of big firefights using Humvees.
Most stuff you expect from co-op was there. You can revive a downed colleague, and if you both die it's back to a checkpoint. To encourage you to play the mode, even if you don't want to, there are unlockable weapons for multiplayer that only become available after clearing co-op missions.
The level design, beginning with interior corridors and ending with confined city streets, was incredibly linear, and also had its fair share of bugs, while being on PS3 (instead of the PC version we've mostly been seeing for months) did it no favours in terms of performance, with the action slowing down during busier sections, aiming getting slow and sluggish, particularly when using a gun's thermal sights.
My co-op partner for the afternoon was Crecente, who despite adoring what he's seen of the singleplayer campaign on PS3 was equally disappointed with the performance of the PS3 in co-op.
Given the fact this was the first time the mode had been shown off, and it's the first time DICE has really tried something like this (and, let's not forget the fact the game is still in DICE's words in "alpha"), here's hoping things can be tightened up a little by the time the game is out in October.
More on Battlefield 3 - specifically, its 32 v 32 PC multiplayer - to come.