I have a Lenovo Thinkpad W520 with 12.10 installed on it. The specifics are:
Linux corellia 3.5.0-19-generic #30-Ubuntu SMP Tue Nov 13 17:48:01 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
It works fairly well, but I have one main issue with it - the brightness controls on my keyboard (or if I go into the display menus) don't work properly. When I touch the brightness down on my keyboard, it shows the gnome brightness control bar going down in the upper right corner of the screen, but it doesn't actually affect the brightness.
Actually, what it does is that it doesn't affect the brightness initially. If I suspend the laptop by closing the lid and then restoring it, it will come back on with the specified brightness setting.
My intuition is that this has something to do with having an improper kernel (i.e. I've heard thinkpads require a special ACPI kernel), but I read (in my previous attempts to solve this problem) that newer kernels (since I think 2.6) had it integrated in the trunk, and thus didn't need a special package.
Not that long ago, I actually upgraded from 64-bit 11.04 Ubuntu, which worked a bit better. Specifically, ACPI actions worked really well there. So, I'm wondering if perhaps I forgot a configuration issue I did when I first set up 11.04.