Here's one step, a crucial one, to making an truly useful instrument from the new button-array keyboards: your midi controller needs a properly configured netbook/laptop. First, you need a loop-back engine, otherwise you computer can only do one thing to your midi input, and you need it do more.
Per the diagram to the traditional intent of midi processing on the computer is to do just one thing: change the input to a different midi signal, or convert it to a neat sound, or perhaps teach a music lesson, but not more.
This is basically due to the ancient (in computer terms), simple original design of midi: the computer was thought of as just another instrument or musical gadget: input one thing, fix it up, and spit if out.
I recommend loopbe1, from some guys in Germany. It is very simple, installs cleanly, and detects feed back.
are other tools available, like Midi-Ox and Midi-yoke. These provide
much more functionality and flexibility, and can help, for instance,
observe midi streams: far more tool than you need.