I've been using a Wacom Graphire3 tablet (a little 4x6 style tablet) with Linux for a few years now. At first it was a bit of a pain to set up, but recent versions of Ubuntu (and Debian too I would expect) have been virtually painless. I've used it mostly with the Gimp and MyPaint (which has great potential btw), and a little bit with Inkscape too. I'm not sure how well it will work for writing text and mind maps. When you use it with the Gimp, you will likely have to do a bit of tweaking (there are plenty of posts on the internets about it) and you'll likely need to start with quite a large canvas to get the resolution for hand-drawing a detailed mind map.
One problem I've found with the Gimp is that it (tablet response) can start to slow down if you're using the tablet with a large brush for large scale photo shading etc. which is really a big peeve of mine. MyPaint seems to handle large brush response *much* better than the Gimp I think. Not sure why.
Anyways, I've found the tablet to be very useful and well worth the purchase. Although obviously I'd love to get a larger one or win the lottery and get a Wacom Cintiq! 
RQ
