Just turn it off before you stuff it in your backpackFans can't function when they are sucking in fabric from the backpack walls, hence the gush of heat you are experiencing
You call this an issue?? I call it lack of CS. When you fry your CPU ,you'll be the first one complaining, Apple sucks!![]()
The "not going to sleep when I close the lid" bug is well known and is not new to this generation of MBP (although I hoped they had corrected it). I have an early 2008 MBP myself and I have this problem happen from time to time. Sometimes you have to do a hard shutdown and sometimes you just open it and it cools off by itself. Don't worry about damaging your CPU as there's a security system that switches it off in case of overheating. Actually it happen to me two days ago and the computer, according to istat, was not really hot (about 60 degrees celsius), but the whole computer, including the outer case were at that temperature because it was inside the backpack.