I upgraded last night from 1.5. I have no interest in rooting, I just wanted some of the new features and apps (navigator, working youtube, pinching to zoom, etc.).
As for the people saying don't upgrade, here's my 2 cents: There is no reason, in my situation, to not upgrade...Either Verizon will release the OTA and I'd get it anyway or Verizon never will and why would I want to be stuck with 1.5 for the next 18 months until I get my "new every 2"? As for my warranty, as stated above, if Verizon does comeout with the OTA then nothing to worry about and if they don't then I'm sure someone out there will figure out how to downgrade it someday and restore 1.5. I really so no reason to not upgrade, unless you're after root, which I don't really care about.
On a related note, I have seen nothing wrong with the update so far except that a lot of the album artwork on Mixzing that used to show up is no longer showing up. Other than that no bugs or issues and I'm completely happy with my decision....(except that in all the upgrade excitement, which I posted about earlier, I deleted all my pics and videos on my SD card).