Yeah the first thing I did on my iPad was disable the battery percentage indicator. It is distracting and ultimately worthless considering how much battery life you get.
Also it is totally inaccurate, the percentage is based on averages and numbers that are dynamic. Basically it's more accurate the higher the percentage, but the lower it gets the less likely it is to actually indicate how much battery you have left. Some people can get down to 1% battery and still get a ton of extra juice out of it, and some people might get down to 10% and see it die really fast.