I purchased FO3 as soon as it came out and blazed through it - really enjoyed it and didn't have any major issues during that run through. Enter several DLC releases and I wound up buying the GOTY edition when it was on sale (cheaper than buying them individually).
Attempted to play through it for the 2nd time with more content to enjoy, and I was extremely frustrated this time around with the crashing (losing progress, and occasionally save file corruption) - I gave up on it.
It's pretty obvious that FO:NV has issues
Help! I'm bored on a Sunday. If you think this game will frustrate me to no end, also take this into account, I usually play something 3/4 of the way through then ditch it (e.g.: GOW3, 40K Space Marine, Alpha Protocol, Deus Ex: HR, Red Dead Redemption, the list goes on and on)