Just be ready to do a -lot- of research, tweaking, and experimenting. Watch a lot of bellydance, choose your form, and then see just what your chosen model can actually do. Generic animations are going to be almost impossible to produce, simply because each and every model has slightly different bones and joint pivots. Not to mention the fact that a lot of body areas simply can not replicate the moves (the actual 'belly wave' could only be simulated with magnets, as it is almost totally a muscle effect, with no skeletal structure in motion to produce it....save for the spinal curving, and the only Poser model with the spinal articulation to actually pull that one off is the DAZ articulated skeleton). The poses may be a good place to start, but in addition to flexibility, you will have to keep velocity in mind, as well. Many of the dance movements, while sinuous, also have elements where motions occur with sharp rapidity. A spline interpolation would make the movement 'mushy', for lack of a better term. You also need to pay a great deal of attention to the hands and feet, and no one has ready made motion files for those. Keyframe animation is your only choice there.