I was playing MW2 last night and I joined a free-for-all game in Invasion. There was strange writing at the side of the screen and there was a tower of ammo crates with turret-guns on top in the middle of the little square with benches and palm trees.
I soon got shot (as usual) and respawned in the tower, shot the 2 guys who were also in there then got shot by someone else who had respawned in there. Then the game got kicked as there were "too many variables" (or something like that) and the game lobby closed.
I managed to rejoin and in the next game my gun had a laser sight and a couple of the other players names appeared on the screen to show where they were. Also, when the score came up at the end, the font wasn't right.
I've only seen this once before. Someone was just spinning round and round firing their sniper rifle and hitting everyone in site but the game lobby closed before I could work out what was happening.
So, what was going on? If it's some sort of hack, I hope it doesn't become the norm. I'm bad enough as it is.