> the gallery usually does a LOT for their 50%. Basically they take over the "business development" work -- all the schmoozing, the selling, the legitimizing.

This, of course, varies. An interesting/tricky part is that the gallery acts simultaneously as a manager, agent, and distributor of the artist's work. Imagine if Brad Pitt worked with the same company to handle his day-to-day affairs, negotiate his fees, and then sell the resulting movies. Not saying it's a conflict of interest, but it is an oddity of the art market.