After a quick download and 1-2 minute installation (on a special screen with the App Store logo and the linen background), my Retina MBP asked for my Apple ID for iCloud. I didn't provide these in the initial setup but did so later. Did this happen to anyone else? It seemed really strange because it appeared as if I were being asked to set up OS X again.
Battery problems fixed! (sort of)
On Retina MBP, battery is changing much more than it did before, but it is reporting better usage times. I saw 8+ hours for the first time, and it has remained between 7:00-8:45 for several minutes. This, however, still seems too unstable to be informative. Perhaps a full cycle will make it more accurate.