As a graphic designer I have been using a graphics (Genius) tablet for a number of years. I find it a very powerful, precision tool for both graphics and replacing my mouse. it offers a far higher level of control than a conventional mouse and has user-defined buttons as well as 'hotspots' on the tablet. We use it with CorelDraw, Illustrator, PhotoPaint, Xara3D etc. but really do not use its full capabilities.
On the down side, I keep losing the 'pen' and seem to spend a lot of time looking for where I left it!
Nikon Coolpix 995
Nikon FC-E8 Fisheye
Panoweaver 3 (& 4 trial)