While the final version of iOS 5 is still not out yet, the beta version of the great iOS is causing iPad to overheat. The full version is slated to be released sometime in the late autumn, but right now, it can be downloaded by the developers that are registered with Apple.
I obtained the iOS 5 for iPad from you-know-where (torrentz.eu/search?f=ios+5+ipad) and found that my first generation iPad reached to the point where it was hot like a frying pan that has been on gas for an hour or so. Interesting, the system turned Wi-Fi off (to prevent the wi-Fi chip from getting fried, perhaps?). Of course, I tried contacting Apple about it and they totally refused to comment on the issue.