I am going to keep talking about this since I hope one day the ps3 A:CM players will come out!
Last night there was no one on besides a couple who were absolutely thrashing us. The group of marines would not get together. This is a real problem with playing marines. They start out together but respawns are not and the marines generally can only survive as a group. Sure a well placed claymore or jump and grenade might keep you alive but xenos will generally run the table on a group of solo marines. I don't have a headset (lost it somewhere?) but it is totally a requirement for anyone who seriously wants to make a stand.
As xenos the key seems to be speed and diversity. A group of xenos with a spitter or two and a good lurker backed with fast warriors and even the most strategically placed marine stand will fall; deadly....
Anyone have any good tips? I am a pretty consistent player but never really rack up more than about 15 kills. I don't really see what the 30 kill players are doing differently they just seem to do it much better. I find that as a marine I can't turn fast enough to take on a xeno to my right or left but other players have no trouble with it when I play as a xeno. One guy is amazing with the lurker jumping to a wall then pouncing which I find so buggy I end up facing the wrong way stuck to the wall as marines mow me down. A:CM has one of the best multiplayers though not many useful weapon options for marines and buggy xeno classes other than the basic warrior.