What's your point? Check the many threads on this very forum about iPhone 4S heating up. That's what these phones do.
No, not really.
I've owned a 3G, a 3GS, a 4, and 2 4S's (one for a couple of weeks, the other for about a month now). In all of that time, subjected to the same treatment and the same conditions, I have had maybe 2 or 3 spontaneous reboots.
My GNex would literally reboot at least once every 2 days, and sometimes as much as twice a day. Go on the various forums and check it out. It's endemic to the GNex.
That was when I was lucky, of course. Other times, a system process would crash and a dialog box would pop up informing me that this system process had stopped responding. Unfortunately this often happened while it was in my pocket and I wouldn't know about it. Double unfortunately, this system process seemed to have *something* to do with the radio modem or 3G link, because after it crashed, the phone wouldn't be on the phone network anymore. I'd walk around all day never getting emails and missing phone calls until I looked at the phone and realized what had happened.
Other times it would be asleep for a while and the touch screen would die. I could activate the screen by touching the power button, but the menu itself and the unlock screen would be inaccessible - the touch screen just wouldn't respond. Usually about a minute or two later it would crash and reboot, so maybe that wasn't so bad.
All I can say is it's a damn good thing that Apple kit isn't this flaky - I got pretty damn good at ripping open the GNex's back cover and popping the battery out and in to reboot it, and I don't know what anyone would do if Samsung used built-in batteries.
Ok, so I'll admit, the GNex might not be the most representative phone in the Android world. But my wife's Nexus S is pretty flaky too, with the intermittent crazy text cursor, email weirdness, and generally poor battery life.
Unlike iPhone, SGSIII uses CPU manufactured with 32nm process (45nm for iPhone) which reduces power consumption. We'll see how it works. And your GNex is faster at many things than your iPhone 4S (as was SGSII): web browsing and app loading being two important ones.
Web browsing with a few select sites, maybe. App loading, not so much - definitely not with the apps I use.