As you'll see below, I am running 64-bit Debian 7.0 Wheezy (Testing). I had been having this problem since I upgraded to Wheezy from the initial Squeeze installation. I found that somewhere down the line I installed from and/or upgraded to some software in the Unstable repository.
Notably, acpid. I noticed in my logs that acpid disconnections always coincided with gnome-shell's freezes. And after downgrading acpid to the version from the Testing repository, I have yet to have gnome-shell freeze. -- System Information: Release 7.0 (wheezy) 64-bit Kernel Linux 3.2.0-4-amd64 GNOME 3.4.2 Memory: 3.9 GiB Processor: AMD Phenom(tm) II X6 1045T Processor × 6 Available disk space: 60.2 GiB Foreign Architectures: i386 Shell: /bin/sh linked to /bin/dash -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org