How do I recover my Angry Birds progress!
Angry Birds save data is stored to /data/data/com.rovio.angrybirds/files.  I don't believe it's backed up to Google.  Normally all that's backed up is your list of apps, certain settings, contacts, etc.  So your wipe data would have erased it.

I always use Titanium Backup to save my apps and their data.  And when I do something risky like flash a beta ROM that might wipe the phone storage, I back up Titanium's backup folder to my PC.