I've played it for over 70 hours & it hasn't frozen on me.
Sometimes I think the freezing glitches are due to the hardware not the software.
Maybe it is Volition's fault for only testing it on dev kits & new 360's.
They should have maybe also tested it on a load of crapped out 360's too, and also some 360's they've emptied a hoover bag out into, to make sure the game will run perfectly on every variation of Xbox 360 there is.
They should have also written code that can still be read when the disc is scratched & has sticky stuff on it, magic invincible code.
I've noticed a few funny occurrences, like a woman falling out of the sky, or more likely jumping off the roof, outside the plastic surgeon's.
Also guys in jumpsuits falls from the sky & keeps landing in the same grave in the cometary, which is pretty funny & also I think, intentional.
Maybe there have been a few other bugs too, but none that I've really noticed or which have made the game unplayable.