Yup, it seems there's no other way to root a dinc2 except from 2.3.3.
If you're on 2.3.4 I think that means you'll blow away your phone - all tweaks and apps.
You won't have to reactivate, though. Your network will recognize your handset regardless of the OS you run.
I'm still on my Droid 1, studying up on how to hotrod my dinc2. I won't lose anything important, but I feel for anyone who's had their phone for a while before diving in. You can't just root, you basically have to commit to a new ROM.