I'm sitting here typing on a mid-2012 Macbook Pro(9,1, 2.3ghz, 512gb VRAM, HR-AG screen, 1TB Evo) that's currently set up to dual boot Sierra and Mavericks. This is my main computer, so I can't play with Sierra THAT much. Unfortunately, it's one of only two I have that will run it officially, so I can't offload my pre-release testing onto my faithful white Macbook or one of my other computers I usually use. In any case, sitting here in Mavericks with a bunch of programs running and using Firefox, the computer is running quite comfortably. Granted I'm not doing anything too difficult, but the CPU is at 36ºC and the case bottom at 29ºC. While doing much of the same in Sierra earlier(just light web browsing, and with fewer background programs running) I noticed that the computer was getting uncomfortably warm along with the fans ramping up a lot. I didn't have a temperature monitoring program installed or active, so can't give numbers. Like I said, though, it was hot enough that it was uncomfortable to hold on my lap-and that's with a Spec case on the bottom. Has anyone else noticed this?