Some Key iOS 6 Features Not Working on iPad 2 and new iPad
IntoMobile

Apple rolled out the iOS 6 software update for the iPad 2 and the third generation iPad starting Wednesday. Not all 84 million iPads sold by Apple would be receiving iOS 6 and its 200 new features as the new software does not support the original iPad. Siri, the app previously exclusive to the iPhone 4S, will now be available on the iPad 3. Siri and FaceTime over cellular both work on the third-generation iPad, but not the iPad 2. iOS 6's new feature of allowing users to take 240-degree panoramic photos doesn't work on any iPad.

What Else You Need To Know

  • iOS 6 is available for download through iTunes or wirelessly via an over-the-air update.
  • Additional features from iOS 6 include an improved Siri (now able to open apps), a new Google-free Maps application with turn-by-turn navigation, integrated Facebook, shared photo streams through iCloud, and Passbook app for storing tickets and coupons.
  • Installing the software update is straightforward, but iPad owners may have to wait for 24 to 48 hours before upgrading as Apple servers are usually busy on the first day.
  • Aside from the iPad 2 and iPad 3, iOS 6 is available for the iPhone 3GS, iPhone 4, iPhone 4S, iPhone 5 (already pre-installed), 4th gen iPod touch, and 5th gen iPod touch (pre-installed), although not all features will be available for all devices.

Other sources

In the event something goes wrong with your update, you'll always want to make sure you have a current backup. If you haven't made one recently via iCloud or iTunes, make sure you do before proceeding. - Allyson Kazmucha, iMore  
There is really no reason to skip the iOS 6 update. Well, unless you want an iOS 6 jailbreak. For that you may need to wait a while. - Josh Smith , GottaBeMobile  
Other
iOS 6 available for download starting at 1pm ET
Android Central
How to update iPhone, iPad, and iPod touch to iOS 6 via iTunes  

In the event something goes wrong with your update, you'll always want to make sure you have a current backup. If you haven't made one recently via iCloud or iTunes, make sure you do before proceeding.

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