Today Apple released iOS Beta 2 for developers, one main feature that’s enable in iOS 5 beta 2 is the Wi-Fi Sync features which will wirelessly sync iPhone, iPod Touch and iPad with iTunes.
You must be running on iOS 5 Beta 2 on your iOS device and iTunes 10.5 Beta 2 should be installed on your computer for Wi-Fi sync feature to be enabled and a Wi-Fi Connection. You will also need a USB cable for the initial sync. Wi-Fi Sync feature works on Mac systems for now but soon it will be enabled in Windows too.
After meeting those requirements, follow these steps to get Wi-Fi sync working:
1: Install iOS 5 beta 2 on your iOS device.
2: Install iTunes 10.5 beta on your computer.
3: Plug your device into your computer and open iTunes.
4: In iTunes under the summary tab for your device, enable “Sync over Wi-Fi connection” and sync your device via the usb connection.
5: Untether your device from USB, and your device will still be recognized by iTunes!
6: Drag and drop files from iTunes to your device, and wipe the tears from your eyes as you watch Wi-Fi sync work for the first time.
Check the Video Tutorial on how to enable Wi-Fi Sync in iOS 5: