I had a discussion with my cousin, who is in a top 10 ranked Halo clan, about this last night. He said he didn't care really, just thought we'd look pretty goofy playing w/ a kb/ms while everyone else is using controller. I reminded him it was obvious he doesn't attend a lot of Lan parties
The only thing that bothers me about this is does Halo allow you to disable “auto aim”? That would royally suck trying to aim w/ a mouse w/ that thing on.