It seems that RIM may have un-officially released their Media Sync Application, which allows you to sync your iTunes library with your BlackBerry. The folks over at BerryReview seemed to have found the file hiding on one of RIM's servers. This should mean it will be officially released soon, although we aren't expecting it until Desktop Manager 4.6.
Apparently they were able to transfer 260 songs with album art in about 10 minutes to a BlackBerry. That's not too bad at all!