experimental results of Cyper:
Follow the wizard settings here once, and later as soon as the ipad and Mac all turn on WiFi,
Then open itunes from your Mac, and you'll be pleasantly surprised to find that the ipad is connected (without plugging in the data cable)
PS: The prerequisite is to open itunes from your Mac every time.
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How to set up ITunes Wireless Sync
1. Make certain this your computer and IPhone, IPad, or iPod touch is connected to the same Wi-Fi signal.
2. Connect your IPhone, IPad, or iPod touch to a Mac or PC via USB. Launch ITunes If it doesn ' t do so automatically.
3. Highlight your IDevice in the sidebar.
4. Click "Summary" in the menu bar. Scroll down to the ' Options ' section.
5. Check the "Sync with this (IOS device) over Wi-Fi" box. Click "Apply."
6. Detach your iPhone, IPad, or iPod touch.
7. Initiate an itunes Wi-Fi sync by tapping Settings > General > ITunes wi-Fi sync > Sync now on your iPhone, iPa D, or iPod touch. Or, plug it into an outlet.
Enjoy your wireless freedom!
For more, see how to Get Apple's iOS 5 as well as PCMag's full review of iOS 5 and we hands on with Apple ICloud. We also has a guide in how to Get ready for the New iPhone 4S.
How to set up ITunes Wireless Sync