Unless you take advantage of hardware vertex animation, which is either going to severely limit the number of joints you can animate, or force you to write a complex shader to do the animation, then Panda will perform the animation on the CPU. This requires having a different copy of the vertex data for each differently-animated actor.
Note that this is not really too bad an arrangement. You’ve got lots of memory on the graphics card for vertices (the vertices are typically something like 1% of the total memory of your scene; the vast majority of graphics memory is taken up by textures). You might as well use that memory. It doesn’t do any harm to have 10 different copies of one particular actor’s vertices, and it will still render as quickly as if you were using the same vertex data 10 different times.
David