I hate updating major revisions (10.6.x to 10.7) or from beta to release. That's just my personal preference but there's a ton of stuff that is either leftover that is useless (best case) or leftover and doesn't work (middle case) or leftover and causes the system to not even boot up anymore (worst case). Assuming Apple lets those with official DP releases upgrade, you can probably try it but be prepared to start from scratch if it fails and leaves your system unstable. I don't know how DP --> final upgrades worked in the past.
I suppose I could do it again & with a backup to hand all should go well.