>>>> "In my case my new iPad it was running WARM, i did reduce the brightness a bit, at first the charging was long, but today, things are cooler, full charge in 3-4 hours - all is happy." <<<<
I think that this is one of the most important points in the entire thread.
If you're freaking out, read that quote again and try doing the same thing.
My new iPad was sort of warm (not what I'd call hot) - my main concern was that it was taking forever to charge when in use – and I posted about that here a couple of times. Since then, I've turned down the brightness a bit- it had been set at or near maximum. For me at least, a modest reduction in brightness has had a big affect on warmth & charging time. Before, I could hardly get it to charge while in use. Now, it seems to charge in use almost the same as the iPad 2.
I have to admit, I was freaking out a bit myself – thinking that I couldn't top off my battery while using the iPad. I feel a little silly now. It looks to me like the new iPad needs a disproportionate amount of power at the 100% brightness setting. At least in my experience, it doesn't need to be turned down much to save a lot of power.
It's new hardware – only five days old for us. There are a few idiosyncrasies to learn about. The display is great- literally superior to anything else in the world. For me, the benefit of Retina is worth a small learning curve & usage adjustment. I was actually fairly worried for a couple of days there – but not anymore.