Got some much-needed Xbox Live access last night, and played my first round of multiplayer. My three Mutons against his two snipers, an assault, and either another assault or a support, all with lasers and basic gear. In the end I lost because his second sniper had snapshot, and nailed a hit on my floater, despite being in full cover, but I can confirm that in my first bout as the bad guys, the XCOM project lost three valuable soldiers. And judging by how I react when ONE trooper goes down, I'd say that's gotta sting.
Yes, I know multiplayer troops are different from singleplayer and killing one online makes no difference in the game, yadda yadda yadda.