Such specs for hard drives are nothing new for desktop hard drives, but for notebook hard drives (2.5" form factor) they are state-of-the-art. Via Anandtech, Seagate and Hitachi released 100 GB / 7200 RPM drives a few weeks ago. According to reviews and head-to-head comparisons, it looks like the Hitachi drives have better performance, are cheaper, and are more robust. As the specs and capacity of 2.5" drives improve, I think that portable 2.5"-based RAID arrays for data backup are not too far off in the future. For reference, here's an article on notebook-drive-based RAID using 5400rpm drives a few months back from Tom's Hardware.
The drive in my new T42 thinkpad on order is a Hitachi 60GB/7200. I will be posting some comparative benchmarks between that drive and the one in my present T40 (an 80GB/4200) once i get the new machine. There's a comparison of 7200, 5400, and 4200 rpm drives at LaptopLogic that I can compare my results to.