AirPlay Mirroring in iOS5 has been met with great enthusiasm from journalists and developers attending yesterday's WWDC keynote. Scott Forstall, Apple's iOS software head briefly described it during the keynote talk:
"AirPlay Mirroring, you can now mirror your entire iPad 2 right to your television, wirelessly, using Apple TV"
AirPlay now supports video mirroring, you can "wirelessly -- and securely -- stream whatever's on your iPad 2 to your HDTV via Apple TV". This feature pretty much replicates the functionality of Apple's $39 AV Digital Adapter which lets you output whatever is on an iPad's screen to an external display using HDMI cable. "Everyone in the room sees exactly what's on your iPad display up there on the big screen -- even when you rotate iPad from portrait to landscape or zoom in and out on photos", Apple explains. One caveat: AirPlay is compatible only with the second-generation Apple TV.
Here's a video of AirPlay Mirroring in action: