I’ve been the lucky owner of a Thinkpad X61s for a bit more than a week now. It’s a light and small 12.1 inch notebook. It’s structurally very solid and has got almost the same full size keyboard as my 14.1inch T60. (The enter, tab, shift and alike keys are shortened in width).
Internal mic/speaker and external jacks; video; DRI and AIGLX; USB; PCMCIA; wireless; fingerprint reader and ethernet all seem to work just fine. I haven’t tested the firewire, ssd slot, bluetooth and n-capabilities of the wireless yet.
In comparison with my T60 the volume and the backlight buttons aren’t hardware controlled. Gnome recognizes the volume buttons, but not the backlight ones. I’m still working on those.