I found this today and I'm playing to find out how useful it can be: Wirelessly Sync Music to Your Android Phone - Winamp Blog
Doubletwist with Airsync does the same in a more elegant fashion. It does cost a couple bucks though.
I have tried WinAmp and DoubleTwist. Doubletwist works much better and the Airsync is faster than doing it via USB.
I bought it when it was $0.99. I think it is $3.99 now. Sent from my Ideos S7 using Android Tablet Forum App