OK, here's my "it's been 2 days" review.

It's small, though in my mind, not significantly smaller than the X31. In fact I had to put the two side by side to really get a feel for how much smaller the X40 is.

Build quality is consistent with other thinkpads. Keyboard is thinkpad quality.

Battery life reminds me of my X20... you're not buying this for battery life, though.

Screen is good.

All in all, it's a tiny thinkpad. Personally, I'm in love with my T41 for different reasons. I'll stay with the T41.

Let me know if you have other questions.