The black ones are considered more desirable, but the white ones are harder to find (and if what I'm told is true, the production numbers were substantially lower, which is why that's the case)
I think I'd prefer a "beige" one because the labels would be more resiliant (that, and because everyone is distracted over the black ones, too busy to give the "old ugly beige" ones a glance). I do like the sliver logo though.
My guess as to why the black ones were produced more, was, to match with the whole thinkpad scheme. IBM did create a few beige products for awhile (like the cool beige LCDs and the beige netvistas). It would be great to have a beige thinkpad with a lavender trackpoint and blue logo. Even though I'd probably be the only customer, it would look nice (to me).
Beige is easier to see and lights up the room with its beigyness.
