The quickest way (and really the only way) to charge your iPad is with the included 10W USB Power Adapter. iPad will also charge, although more slowly, when attached to a computer with a high-power USB port (many recent Mac computers) or with an iPhone Power Adapter (5W). When attached to a computer via a standard USB port (most PCs or older Mac computers) iPad will charge very slowly (but iPad indicates not charging). Make sure your computer is on while charging iPad via USB. If iPad is connected to a computer that’s turned off or is in sleep or standby mode, the iPad battery will continue to drain.
Apple recommends that once a month you let the iPad fully discharge & then recharge to 100%.
How to Calibrate Your Mac, iPhone, or iPad Battery
At this link http://www.tomshardware.com/reviews/galaxy-tab-android-tablet,3014-11.html , tests show that the iPad 2 battery (25 watt-hours) will charge to 90% in 3 hours 1 minute. It will charge to 100% in 4 hours 2 minutes. The new iPad has a larger capacity battery (42 watt-hours), so using the 10W charger will obviously take longer. If you are using your iPad while charging, it will take even longer. It's best to turn your new iPad OFF and charge over night. Also look at The iPad's charging challenge explained http://www.macworld.com/article/1150356/ipadcharging.html
Also, if you have a 3rd generation iPad, look at
Apple: iPad Battery Nothing to Get Charged Up About
Apple Explains New iPad's Continued Charging Beyond 100% Battery Level
New iPad Takes Much Longer to Charge Than iPad 2
Apple Batteries - iPad http://www.apple.com/batteries/ipad.html
Extend iPad Battery Life (Look at pjl123 comment)
New iPad Slow to Recharge, Barely Charges During Use
Tips About Charging for New iPad 3
Prolong battery lifespan for iPad / iPad 2 / iPad 3: charging tips
iPhone, iPod, Using the iPad Charger
Install and use Battery Doctor HD
In rare instances when using the Camera Connection Kit, you may notice that iPad does not charge after using the Camera Connection Kit. Disconnecting and reconnecting the iPad from the charger will resolve this issue.
I drained the battery to shut off and recharged without help. Finally in desperation I did a full restore which appears to have helped. The only reason I did the restore was because the IOS 6 update broke email which led me to believe that something else might have been corrupted in the initial IOS 6 upgrade. The restore redid the IOS 6 update and nothing was broken this time around and the battery issues seem to have dropped off to a point where it is almost as good as it was before the upgrade. If I see more issues with the battery pop up I will add to this thread, otherwise you can assume it case closed.
PS: That site survey is a waste of time. You would be better served to ask a question and have a text field for responses. The survey just gave me a feeling you were asking the fluff questions to fullfill a requirement.
For me it was simple: I had the problem first with my phone two weeks ago: Remove Facebook and bingo. Back to normal. Suddenly the same problem with my Ipad. Removed Facebook: Well what do you know, the battery is normal again. The other major side benefit...you get about 5 hours of extra time a day because you aren't checking Facebook all the time. It's a win win!!!!