Lenovo has actually been shipping this kind of screen for a while now. Getting the pen out, putting it back, getting it back out, putting it back, and deciding over and over which input method is better gets old fast.
There is definitely a market for this, but it's primarily geeks and somewhat geeky students.
I don't recall any multi-touch lenovo tablets that old. What kind of software was it used for?
N-Trig was the company that worked on the technology.
http://vimeo.com/5388897
There might have been other's but I think this is the onw MS invested in.