Finally, after more than 3 years (http://oldforum.freegamedev.net/index.php?t=msg&goto=23069&S=0544c6d9ca2945479cf0035ef98957de), the SVN trunk of STK has support for the wiimote (for Linux only for now)! (if you compile with the USE_WIIUSE CMake option).
There is still some fine tuning to do, and I would be pleased if I could get some feedback from the people on the forum. Right now I think the turning with the accelerometers is not reactive enough, and the mapping of the keys is probably going to change.
Samuncle, maybe you can set the -DUSE_WIIUSE option to the nightly builds so more people can test?