News of this was buried inside another thread.......
I searched on the web and confirmed it's true.............looks like it's compatible with iPad 3 units also.
See information below....
Apple confirms that 12W adapter will charge iPads quicker than older 10W adapters
The morning of Apple’s iPad mini event earlier this week, we told you there was a handful of new accessories coming including four new Lightning adapters and a 12W USB power adapter. We didn’t hear much about them during the event, but the new cables and adapters have hit Apple’s online store now, including a Lightning Digital AV adapter and Lightning to VGA adapter, with most shipping in “2-3 weeks”.
On the product page for the new 12W USB charger, Apple confirmed it would indeed ship with Retina iPads. With the new fourth-gen replacing the third-gen iPad—that would essentially cover just the iPad 4. It is, however, selling the adapter by itself for $19 online and listing compatibility with iPad 2, iPhone 4S, and iPod touch fifth-gen and up. Many readers have wondered whether the adapter would allow for faster charging with the iPad 3 and fourth-gen iPad. A big complaint among third-gen iPad users is that the device took up several more hours to charge than previous generations due to its larger battery. Also, on Apple’s discussion forums, some users asked if a software update would be required for the iPad 3 to draw additional power.
When we asked Apple about the 12W adapters, we were told the following:
“We don’t have an exact percentage of how much faster it would charge but you should see an increase in speed.”
It would make sense. For example, an older 10W iPad charger charges an iPhone slightly quicker than its own. In case you were wondering, Apple also told us that the iPad mini would come with a 12W adapter as well, which means we could see much quicker charges for Apple’s smaller tablets in addition to the new Retina iPad.
Apple’s new 12W USB Power Adapter is available right now from its online store for $19 and shipping in “1-3 business days“. Word has it that Apple will also exchange iPad 3′s purchased in the last 30 days for a new fourth-gen.