1 freeze
I was swimming around and got stuck under some areas that needed invisible walls. (no biggie just needed to fast travel out)
some weird thing where when i exited helios one, the junkyard lady and her dogs and some random molerats spawned on top of me and attacked me. (just needed to load the autosave)
every once and awhile people will talk but their lips wont move.
sometimes my cowboy repeater will take a while to start shooting (however i think its only when i get poisoned)
so.. yea.. thats about it. No more glitches than any other game. halo 3 and reach included.