He links a picture that says 2.9+ lbs., which I'll guess is possible but reeks of dodginess given that 90% of the major reviews (cnet, pcmag, engadget, laptopmag, all quote 3.3 (or 3.5) pounds for 6 cell configuration, these are easy to find with google, here's one that weighed it himself:
I'm guessing 2.9 pounds might be for the originally planned 3 cell battery version which may be offered somehow but is not configurable through the online order at lenovo.
http://www.studenttechguide.com/2011/08/lenovo-thinkpad-x220...
I'm guessing 2.9 pounds might be for the originally planned 3 cell battery version which may be offered somehow but is not configurable through the online order at lenovo.