My T400s isn't liberated yet but Technoethical will be working on it during
summer. When I have it I can make a comparison.
As for now I can shortly state that between the 64 bit Thinkpads there isn't
much difference. The MacBook responds a bit slower e.g. to open the browser
windows and such. The MacBook is the only one (of those tested for that) on
which Handbrake would rip dvds. I have no idea why, but on the x200 and the
t500 I had to install and setup css.
The MacBook does get quite hot, but it doesn't seems to be a problem. And its
screen is superior to the other's.
Well, as said I can make a better comparison when the T400s is flashed with
libreboot too. If you have specific questions in mind or specific ways to
test in mind, please tell me.