Reminds me I have to back up my saves. It started working when I switched to steam offline mode, except from the random AI glitch now and then - I've had a gecko charge at me, and just keep going forwards when I side-stepped, and keep going forever. Radscorpions has a tendency to sink partially into the ground (but still being lootable, luckily), and there's some invisible walls on the NCR correctional facility towers. Other than that, no bugs or glitches. There's a problem with meelee-based enemies not figuring out how to traverse z-levels at times, but that's probably more of an engine failure than a bug.
This game is great fun! The western feel is pretty well done, the combination of western and the fallout universe is perfect. The fighting is certainly better than in F3, especially in hardcore mode, which is great in itself. Ammo recycling and the other kinds of crafting is good, but doesn't feel compulsory. If Obsidian manages to fix their damned bugs, New Vegas will be a strong all-over GOTY challenger.
And goddammit Nightkin doesn't award enough XP compared to their toughness and damage potential. I managed to take them down with Stealth-boys of my own, but meeting two of them lost me as much HP as 8 gang members, and awarded me 1/6 of the XP.