The Apple Support Communities are an international user to user technical support forum. As a man from Mexico, Spanish is my native tongue. I do not speak English very well, however, I do write in English with the aid of the Mac OS X spelling and grammar checks. I also live in a culture perhaps very very different from your own. When offering advice in the ASC, my comments are not meant to be anything more than helpful and certainly not to be taken as insults.
Probably not, because the charger gives the device what the device askes for, up the the limit of the charger. The iPad 3 will ask for 10, not 12.
See the Learn more section.
This new charger is compatible with the iPad 1, iPad 2, iPad 3, iPad 4, and many other devices. Since it supplies more power it will charge all the iPad models faster than the old 10 watt charger.