Performance issues and crashes occur with main, sometimes with more ferocity than others.
Most common for me are the quest bugs. I just updated my "Skyrim isn't Game Of The Year Worthy" post by replacing my map issue (which was really just usability fail) with a bunch of vids on YouTubes of others running into quest breakers. Invincible spiderwebs, UI freezing the game, all sorts of fun: http://cathodetan.blogspot.com/2011/12/why-skyrim-is-not-game-of-year-worthy.html
I enjoyed the game, certainly got my money's worth - but at the end of the day it's more than slightly disappointing that Bethesda can't deliver technically solid games. Next time I'll certainly be waiting at least until the game has been out for 4-6 months, and probably buy it used.
