I agree, buggiest ever, by a HUGE margin. There are always problems (that's what you expect), but not like this. I've run every beta since 4.0 beta 1, and had to restore exactly zero times. I've had to restore three times in the last 5 days. Mail--historically one of the strong points of the iOS platform--is also a complete mess.
For reference: Last week makes 20 years in IT for me (currently managing IT Ops for a mid-size company), and I've been formally alpha/beta testing software since NT 4.0 Beta 1 in 1995 (still have the CDs for beta 2). I'm not bitching about the problems because that is literally what I signed up for. But based on my own experience, this is one of the least-polished formal beta products I've interacted with. It's really more of an alpha from a quality perspective, IMO.