Most desktops would be hard-pressed to cook themselves through a software/firmware hack unless significantly (stupidly) overclocked. In contrast, lots of mobile devices could cook themselves with such hacks even without any overclocking.
There's also a significant difference between firmware and just installing software. The PC manufacturer and MS expect you to install any old software on that windows boxen. Apple did not manufacture the iPad with that expectation, and they were up-front about this.
If you want a hackable tablet, there have been plenty of options around since 2001! I know, because I have one!
The only thing you could do is run a process at high CPU load for a long time, and you can do that in the App Store by plugging the device in and letting it sit there with a game running.
Please note that the iPad jailbreak (unlike the ones used on iPhones) does not actually modify the bootloader and only has minimal kernel access (changing things that, frankly, would make it use less CPU load as it no longer validates signature certificates on binary code it is loading).
(Also, there have been plenty of options since long before 2001, and I know because I have those ;P. Check out the Compaq Concerto running Windows 3.11 for Pen. Frankly, I wouldn't call the iPad a tablet, and neither does Apple: pens are a defining characteristic.)
- Jay Freeman (saurik)
[on the various jailbreak teams, developer of Cydia]
There's also Android tablets aplenty in the works. Thank you very much for your work on Cydia, I am a delighted user of it on my 1st gen iPhone.
The old tc1100 supports basically 90% of the use cases for my iPad, but the iPad is just more comfortable to use, particularly since it lacks the stylus. (With the one exception of drawing.)
Also, just because the jailbreak itself doesn't cause more CPU use, this doesn't mean that the jailbreak couldn't enable something thermally harmful. It's also not reasonable for Apple to have to determine forensically that you didn't harm anything -- it's impossible to prove a negative! Now, if someone was playing a game on an non-jailbroken device plugged into the charger and fried it, they would be entitled to satisfaction from Apple since they were running it on the terms Apple sold it. If you don't like these, either don't buy the device or take the risk of not having the warranty to fall back on. The similar physics of these two situations isn't the issue here, it's all about the legal terms of the sale.
There's also a significant difference between firmware and just installing software. The PC manufacturer and MS expect you to install any old software on that windows boxen. Apple did not manufacture the iPad with that expectation, and they were up-front about this.
If you want a hackable tablet, there have been plenty of options around since 2001! I know, because I have one!