It turns out that all you need to provide is a launch image of the appropriate size. Xcode 4.5 should provide you a build warning saying that you're missing a Default-568h@2x.png image. If you allow it, Xcode will provide you with a black default view. However, you should replace this with a launch image relevant to your application :)
Note: I didn't actually cover this in the video, however there are some subtle rules regarding rotation in iOS 6.
shouldAutorotate and supportedInterfaceOrientations are only called on your rootViewController and any container controllers.UITabBarController or UINavigationController to provide this behavior, or.../rootViewController a container controller that contains nothing but your tab bar or nav barAs soon as I find an authoritative source for this behavior, I'll link to it here.
In a couple of my applications, custom background views were not showing up. You should now use the UITableView setBackgroundView: method.
Any 3rd party static libraries you are using might need to be updated to include an armv7s slice. This includes Flurry analytics, TestFlight, Urbain Airship and more. If you want to do some unsupported and unrecommended hackery to do this on your own, you can follow this guide:
Hacking up an armv7s library
If you don't want to do this, then you'll have to wait for an update from the vendor.