Lars Gustavsson, the lead designer for the multiplayer portion of Battlefield 3, restated that multiplayer animations will differ slightly from single player. The single player animations will be Hollywood style dramatization, while multiplayer will be far more functional.
According to Gustavsson, ”In multiplayer, we do an additional pass for animation. In single player you don’t mind if a guard up on a balcony does a Hollywood death - stumbling around a bit before falling over… We’re more than willing to make differences to deliver the best experience in (single and multiplayer)”. Players don’t want to be shot by other players when slowly climbing into a tank; that’s not a worry in the single player campaign.
That’s not to say there won’t be any dramatic animations in multiplayer - everything DICE is doing is to make sure the multiplayer experience is optimal.