I’m currently updating the software for Apple TV from 5.0.2 to 5.1. This is a pretty straightforward procedure initiated from the Settings menu on the Apple TV.
Posting my thoughts on the update shortly.
I’ve been seeing some weird performance loss on my Airport Express router after the upgrade. I’m afraid something’s fishy. I’m investigating further. I have also run into some other problems regarding Photo Stream viewing on my Apple TV. Se more here http://geek.martinwahlberg.com/apple-tv-photo-stream-unavailable