I haven't noticed a difference in the time I have been poking around, but it's there. ( I didn't have any issues with 2.2 anyhow )

The upgrade took all of 2 minutes from plugging in to done... This upgrade is optional it says and doesn't start automaticly. You will have to click the settings tab, then device, then finally device update. This is what you should see at that point.

zune2_3_install_1

From this point it's automatic... Just don't remove the Zune from your cradle or sync cable.

zune2_3_install_2   zune2_3_install_3

And we are done!

zune2_3_install_4