It looks like Apple's new iPad runs a lot hotter than its predecessor, thanks to a beefier processor, bigger battery, LTE antenna, and other factors. Apple says the thermal specifications of the device are on target, however.
In the scope of things that could go wrong with a consumer electronics device, this is probably on the mild side. After all, Apple's iPhone 4 shipped with a list of hardware defects so long, just covering them all accurately was difficult. And don't get me started on the Xbox 360, which should win a Guinness record for "world's buggiest consumer electronics device, ever." The word endemic comes to mind.
But back to the new iPad. According to Tweakers.net, the new iPad runs about 10 degrees hotter than the iPad 2, about 92 degrees (F) vs. 82 degrees for the iPad 2. Consumer Reports, more famous for not recommending the iPhone 4 than for its decades of consumer advocacy, is reportedly investigating. We await their ruling from on high.
In the meantime, Apple says anything up to 95 degrees is fine, and if you read Laptop Magazine as I do, you know that 95 degrees is the limit for what's considered comfortable, heat-wise. So 92 degrees doesn't seem horrible to me. I'll need to test that though.
So far, I've not noticed this issue personally. But I'm going to play a few HD movies today and see whether its noticeable; that's about the only "grueling" task I'll ever put the device through anyway. My guess is it won't even sweat.