Incase you have not seen it.... again more rumor...it was quoted on Twitter by a Microsoft employee (Cliff Simpkins).
It's said, not sure on how true it is, that Devs (you know you guys who unlocked via the offical method) will get Mango 7712 beta (7720 is the claimed RTM) possably in a few days. This should have almost every feature working on it.
Developers to get new 7712 build of Windows Phone "Mango"? [Rumor] | wpcentral | Windows Phone News, Forums, and Reviews
Shocked that this site didn't post new news....Oh, wait...
Edit: If your running Mango now with 4.8 Zune, just plug in your phone, settings, Phone, Update, check for updates....Don't forget to hit thanks !