Alright, fired up the upgrade package - good news for those folks running Bell version of the Optimus LTE - works awesome. I'm running it unlocked on Fido and after letting the OS settle for a few minutes and uninstalling all the AT&T crapware she's running like a well-oiled machine.
The new interface is actually pretty good as well.
Edit: It seems that you have to go in to the display settings at least once to make sure the auto brightness adjustment works. Also, you can display the battery percentage next to the indicator under the "power savings" heading in the main settings menu.