A tablet with a built in stand can be VERY usable with a bluetooth keyboard. The problem with most tablets is, they tend to be underpowered. But, I have always felt a "iPod touch" type tablet with a good CPU/memory/storage and a detachable keyboard would be a KILLER machine. Imagine a Macbook air with a detachable keyboard. The screen could become a BIG iPod Touch experience.
Besides people on this forum, of the 11 that I know off of the board, I only know one that uses this is the primary computer.