I just upgraded to Fedora 16 using preupgrade. However, I had some issues and was forced to revert to the nouveau drivers in order to get the system to run.
Now, the system will not suspend (sleep - it just locks the system and remains on) or respond to the power button. I've checked gsettings and everything appears to be correct.
I've run a yum reinstall on everything that I felt was remotely relevant - gnome power manager, the nouveau driver and a lot more but the problem is still there.