MediaSync has been out unofficially for quite awhile now so it was about time for it to be released. Nothing new seems to be added to this release but let me know if you do find anything. It essentially allows you to sync your non-DRM music and playlists from iTunes to your BlackBerry. You need OS 4.2+ and iTunes 7+ for it to work.
From the MediaSync page:
Your Music on Your BlackBerry Smartphone. It’s That Simple.
Use BlackBerry Media Sync to get your desktop iTunes music files on your BlackBerry® smartphone. Whether it’s a specific playlist from your collection, or a random mix of tunes, it’s incredibly easy to transfer the music you want to take with you.
Music for the gym? A random mix of songs to get you through the day? Whatever you need, it’s easier than ever to get it on your BlackBerry smartphone.
Easy to Update
If you make changes to one of your iTunes playlists, the next time you sync your BlackBerry smartphone and your computer, BlackBerry Media Sync will make sure the music on your device is updated too.
All the Memory You Need
Whether you choose the playlists or have download a random selection to your BlackBerry, you can control how much of your music is synced to your BlackBerry smartphone.
And with support for a microSD card for expandable storage, you can get plenty of free memory to store all your music, as well as the other files you want to carry on your BlackBerry smartphone.