I have 5 wallpapers with GDE /w Hero theme, StarField live wallpaper (which I wouldn't be devastated if I lost, but I guess may/may not be included w/ 2.1). I can use PDANet instead of WiFi Tether, I'm not crazy about the 2.1 launcher we've seen on Droid so far (if it didn't snap into place & scrolled faster, I'd be sold).
So, in a word: Yes, I would upgrade.
Happiness is like peeing your pants. Everyone can see it, but only you can feel the warmth.
Besides, once the official OTA is out the chefs will use it to make even BETTER ROMs (and many of them are using a leaked version). So why bother with the stock OTA? You'll loose more than you'll gain (e.g. OCing, themes, removing stock apps, custom docks ect.).
You are right to be wary. There is much bullcrap. Be wary of me too, because I may be wrong. Make up your own mind after you evaluate all the evidence and the logic. - Mark Rippetoe
This is not the final 2.1 update. Read very carefully, the link the OP posted says:
"now i'm not talking about some custom 2.1 rom, i'm talking about the 2.1 update 1 that many expected to be our official ota update."
He's talking about the ERE25 update that everyone and their brother is modding in the Hacks section, not a final 2.1 build.
My source says we will get 2.1 this month and that it will be delivered OTA.
He is never wrong.
2.1 will come out when nexus 1 is released on verizon