I have had my iPad 2 for about a month and the only differnce from my iPad is that the battery seems to drain more on this one. I did go from a Wifi to a 3g but I have the 3g radio turned off. It seems to drain about 20% more than my ipad.
Adjust the default brightness of your display. I don't know if it is brighter by default on the iPad2 than on the iPad1, but after moving the slider a little to the left I am now getting as good a battery performance as on my old unit.