Ted Roche hits the nail on the head with this last comment about Tablets:
Tablets are a solution in search of a problem. Third Microsoft attempt at Pen for Windows. It's still halfway between a powerful notebook and a PDA - too big for a pocket and too underpowered for a desktop replacement (for you and I, anyway). No question there's a niche, and each generation gets better, but the touchscreen premium still seems high for most of the use cases my clients have.
Having lost my PDA for the time being (due to a cracked screen), it makes me feel slightly concerned about getting a Tablet PC where I'm sure the replacement cost of the screen would be even greater.
Eurocom (http://www.eurocom.com) offers fairly decent machines that are good desktop replacements but I'm still griping about the lack of visibility in Canada.