This turned out to be smaller than I expected, but I suppose I should have realized that. It's closer to the size of a cell-phone than a tablet, so although you can't type on it like a netbook's keyboard you can at least hold it comfortably in your hand and comfortably 'thumb type'.
The keys are a nice rubber and the case feels solid enough in spite of being ultra-slim. I was surprised, however, that there was no page up or page down anywhere on the keyboard. I also found that the question mark didn't work on a second non-playbook linux device I tried.
The charging light didn't come on unless I jiggled the cable that came with it, and the button to start polling is a pain to press. If you bite your nails you'll be trying to press it with the end of a spoon.
Whenever my Playbook went to sleep the connection would be lost but I haven't tried to reproduce this on another device.
It's not a huge improvement over the touchscreen keyboard, but it's a faster, easier to correct mistakes, and while this is connected the Plabook doesn't pop-up the on-screen keyboard.