Something else to consider is that a lot of the development for tablet PCs is taking place in the vertical market (healthcare, supply chain, etc). So you are less likely to see shrink-wrapped tablet applications than you would be to see vendors including tablet functionality in their applications.
To take the healthcare example: a medical facility might buy an electronic medical records system than includes a database component, and application server component, a web server component for remote access, a thick client for desktop PCs and a tablet PC component for use in exam rooms, at the bedside, etc.