Here are the patch notes, from Blues News
Improved stability in online multiplayer matches.
Improved voice chat quality for PCs running Windows Vista.
Improved navigation through game’s menus.
Introduced 6-man party system in the multiplayer game mode.
Balanced several weapons (assault rifles, SMSGs, handguns, shotguns).
Balanced equipment (grenades, flash bang, EMP, stun guns, number of drones in match).
Adjusted aim sensitivity and quick scope.
Fixed map exploits.
Adjusted melee.
Adjusted XP values.