Well I tried to install the leaked 2.1 last week and it went horribly wrong!
I went back to the 1.6 and decided to wait until the o2/Dell release.
I got home last night and saw the triangle with exclamation mark saying there was an update for the phone.
So I backed up again using Mobile Backup II and ran the update.
Left it for about 30 minutes to download and run the update - gave me a satisfying notification sound.
It's been a dream to use since!
Spent this morning installing all my apps via AppBrain - deleting some from the list that I never used.
Loving the live wallpapers ;-)
I know some of you are having problems and I really do feel for you, hated it when my leaked 2.1 wouldn't boot - just sat on the Dell logo screen.
I'm sure if you use the link to go back to the official 1.6 package and try again, it will work at some point.
Just wanted to say that some updates have worked.