Updated the iPad last night. So far the look GUI is completely underwhelming. While its nice to get to the control panel, I cannot stand the look of the desktop folders. I also think they took a step back narrowing the fonts, but at least you can coax them back to nearly "normal". They have removed allot of the colors out of the Safari GUI that used to separate pieces of the menu bar, but now its just grey. Its fun to close apps by swiping up, but its WAY slower than the old way.
The IM screen appears to now display the entire IM list on the left rather than dedicating the screen to the person you're talking to, hopefully there is a way around it.
It is also WAY more finicky about power. I have an 8' cable that i charge the iPad with, and now it complains about not having enough power to charge. It also "seems" to be draining the battery faster... Mebbe not.
I think I'll leave the iPhone on iOS6 for now. Too bad they didn't include a 'Classic' mode like MS did with XP.