As I mentioned, there were apparently sightings of a prototype as far back as last summer, with specs rumored as early as Jan 2004).
Start the rumor mill again. A Tablet PC Buzz reader writes:
WE are trying to decide what tablet to purchase for students 5-12 grade and met with a leasing agent who had just gotten the IBM tablet from them that morning. (He also had the toshiba R15, M200, a motion and an HP 1100 so it was great fun!) He said the IBM is due out May 15. It is 12 inches but looks smaller..looks just like the thinkpad...had a 1.5 or 1.6 processor...it was about 3.5-4 lbs...it felt like the lightest one and was as thin as the motion slate....has a feature to partition off the image we would load and allow us to "reimage" little johnny's from his own laptop....it has 2 batteries in the battery attachment so it gives it 8 hours....it was very thin... We really liked it....the issue for us and the teachers is the IBM (a little scary that it is the first year) and the light weight or the R15 and the big screen..both had comparable pricepoints..IBM was pricing between $1500-1600..with the slice included...
It will be very interesting to see. I'm very happy with my Toshiba, but as I've said it feels a little thicker than it needs to be. In fact, that's probably my only complaint. If the IBM tablet is really as thin as the Motion slate, this one could be killer.
Regardless, I think IBM/Lenovo's entrance to the Tablet PC market is a big move indeed. We'll know we've really hit the tipping point when we finally see the Dell tablet).