I took a look at the Jstamp and it looks interesting. There are a couple of problems, though, the biggest being price. The chip istelff costs $109, almost twice as much as the stampIIsx. They also say that you must have the development kit to be able to program or debug the Jstamp. This costs $300 (but it includes the Jstamp).
Another, more minor problem, is that while the Jstamp has 22 IO pins (if I counted correctly), but only 5 of them sink/source 25 ma, with the rest sinking/sourceing 8 ma. The stamp II has 16 IO pins, but they all sink/source 30 ma. I don't know if the controller needs all the pins to sink/source that much current, but it would be more circuitry (more cost) if so.
A better solution seems to be the J-stamp from parallax (confusing isn't it?
). You can read a liitle about it at
j-stamp.net
It appears that it is pin compatible with the Stamp II, which means that Innovation FIRST could drop it in to the existing design. They would still have to write a new default program, but it would be much easier then a completely new design.