My personal experience is that it never gets more hotter than slightly toasty, and I've played:
- Grand Theft Auto 3
- Shadowgun (the one I paid for hasn't got Tegra 3, and to be quite frank, I really cannot be bothered to fork out money for the same game but fancier water and physics)
- Minecraft
- Modern Combat 3 (utter rubbish, knock-off COD clone for mobiles)
I've got other games like World of Goo, Max Payne, EDGE, and Canabalt HD which I briefly tried, and it's a comfortable experience where you can actually use the touch screen controls nicely, and the screen size is big enough where your hands don't engulf the entire screen. It's actually quite a pleasant experience from the Galaxy Nexus where the screen was huge, but not quite huge enough for playing games or watching TV/Films/Youtube etc.