DoubleTwist has been labeled 'iTunes for Android' for some time but the app's new AirSync feature gives it a leg up on the competition. It has upped the ante by offering comprehensive media syncing over Wi-Fi connections via its new app called "AirSync", which eliminates the need for cables.
Here's how it works: You download latest version doubleTwist of Mac or PC, then install it on your Android phone and either scan AirSync icon to upgrade (if already have) or download AirSync from the Market, or scan the QR code embedded below. Next, your phone give you a passcode. Select your device from the desktop version of doubleTwist and enter the passcode to pair your phone with your PC. Once done, you can select "music, movies, and photos" you want to synchronize and doubleTwist will do the whole thing over your home WiFi network.
It can take a while to transfer all of your data the first time, but once that's done, doubleTwist will detect your mobile device whenever it's on the network and make sure that any new files on your computer or phone are synchronized.