If 2009 was the year of the netbook, the tablet PC should rise in 2010. Where netbooks offered super-portable, affordable connectivity, tablet PCs promise to let us interact with our computers in new ways. The classic tablet resembles a laptop that swivels so that the keyboard is hidden under the screen. The touch screen interface allows for jotting notes, editing text and generally eschewing the mouse. Among techies, rumors have run rampant about a forthcoming Mac tablet (latest rumored release date is January 2010), with Steve Jobs’ disciples salivating at the thought of something like a laptop-sized iPhone. And in September photos leaked of a sleek folding Microsoft tablet. The “Courier” looks like a touch screen laptop with a second screen where the keyboard would be–a leather portfolio, stuffed to the gills, for the 21st century.

With that in mind, I was excited when I heard about the Convert to Touch Duo, which promises to transform any computer into a tablet for $120. After a standard CD-ROM software installation, hardware installation was a cinch–you stick a magnetic “reader” on the top of your screen, which senses the location of the pen. After a five-second calibration, the Duo was good to go. I was pleasantly surprised at its accuracy in reading the pen’s position. Used with Windows Vista’s included tablet software, it does an impressive job at handwriting recognition, even with careless scrawls.

Since it’s not a true touch screen, the Duo experience wasn’t perfect. It doesn’t always pick up pen strokes, particularly in the corners and far sides of the screen, and I had to stop to recalibrate after about an hour of use–I must have gradually knocked the reader out of place.

The other drawback is simple–tablet PCs are tablet PCs. A laptop is a laptop. Putting a touch screen on a laptop does not a tablet PC make. It was a neat experience to navigate my computer by flicking the screen with the pen, but in the end I was still awkwardly reaching over my keyboard–and trying to get over my aversion to actually pressing down on my LCD screen with the pen tip. I liked being able to highlight and scribble notes all over PDFs, but I could only save them as screenshots. I found the Duo best for short tasks like signing a contract rather than annotating a hundred-page document.

When I’m ready to take the step, I’ll seek a tablet PC that comprehensively integrates touch screen functionality with its operating system and user interface. Until then, at $120 the Duo is still dirt cheap relative to buying a brand new tablet PC and it’s an easy way to try out the technology.