Well, I was ridgid binding in Alias for quite a while, so I was overjoyed when Maya came out with smooth binding. For the most part, I smooth bind everything, very few things I would ridgid bind. The only time I ridgid bind is when I'd have say... a snake, that has many, many joints, and when it bends I want some custom deformation on each joint, which a flexor could provide. But I'd still only use it for tests, the final thing I'd probaly smooth bind, and build my own custom deformers. Really, when it comes down to it, they output their deformations in pretty much the exact same way, they just allow you, as the user, to apporach it differently. Ridgid binding allows you to overtransform components, which sometimes can be a real nightmare, while other times, gives you a desired effect. Smooth binding can be copied between skeletons, which ridgid binding can't do, and that itself makes it extreemly usefull in pipleine management... I use that capability extensively. Finally, our plugin guy wrote a cool script that will normalize the weights of ridigid bound characters, "simulating" the results of smooth binding... which has been real helpful in some of our realtime engine exports. Anyway, hope this helps out.