Your last sentence... I'm in the same camp.

I was waiting for the MBP announcement to see if the 13" would be so compelling that it would become the perfect laptop for me, but the keyboard still isn't for me, and I really wanted USB3 and was hoping to lose the CD bay in exchange for more battery.

The T420 is slightly larger than I wanted, but Ubuntu on my T61p is such a sweet thing for development and lifestyle use that the smaller T420 looks really good. If Lenovo had a 13" in the T series spec'd like that, they'd have me instantly... as it is they probably have me anyway as the MBP hasn't moved enough to be compelling to me and I can deal with the slice battery on the T420 for a long weekend of use when travelling. The Lenovo keyboards remain without compare, which I guess means I'm now talking myself into it pretty convincingly. T420 + Ubuntu seals the deal.

Edit:

Just checked out the T420 dimensions, and they're: 13.4in x 9.05in x 1.18in.

It's not bad... a little larger than the new 13" MBP (12.78in x 8.94in x 0.95in), but not by enough to dissuade me. The higher resolution on the T420 is a good trade-off for the extra bit of size.

Am I the only one who absolutely loves the eraserhead on the Thinkpad? It's so nice to be able to use the mouse without taking your hands off the keyboard. (Why netbooks have a tiny, useless touchpad rather than an eraserhead is beyond me.)

My 2009 macbook has been a disaster for me ergonomically. The keys are spaced too far apart and I keep trying to "click" the trackpad, which is killing my fingers. And the limited trackpad space when trying to drag or highlight something long drives me crazy.

"The plastic casing is brittle and just breaks off after a certain amount of time"

This is apparently a known issue with certain models of the Macbook. I had mine replaced free of charge as well, even though I'm out of warranty. Apple is aware of the issue and I'm happy that they at least replaced my case without a fuss.

Your Macbook sounds as though it came from the same batch as my wife's Macbook. The Apple store replaced her battery free of charge well out of warranty and also offered a replacement casing. This could be a UK thing as it's pretty clear that there was a period where Macbooks were being manufactured below acceptable standards, the "Sale of goods act" would apply.

I bought a Macbook about a year after my wife and mine has been absolutely fine, no cracking and still with a good original battery.