Having owned several IBM T-series ThinkPads I've always been a fan. The ownership of T-series has spread throughout the troupe of Linux Training instructors here at Guru Labs as lesser laptops have fallen to the wayside.
I've had my current T42p for almost three years now. I've been very happy with it. The build quality is excellent, and it anyone looking at it would never guess it has been used daily for the last three years. The Linux support is superb. The only problem is that the 2.0 Ghz Pentium-m CPU in it doesn't support PAE so Xen in RHEL5/FC6 doesn't work.
Today I found that IBM has posted details on the new Santa Rosa chipset based T61 laptops to be released next month. I plan on picking one up to replace my T42p. Some of the highlights: