I've been staying in Udaipur for a few months now and have been to Shilpgram a couple of times - every time I go, it's more or less deserted of artists (except at the festival, I'll get there in a bit). I know plenty of other people who've been and come back laden down with stuff, but for some reason nobody wants to sell me anything! What is there is lovely, but there's not much choice. I guess it just depends on how many artisans are there on any given day.
The festival, on the other hand, was phenomenal. Hundreds and hundreds of stalls from all over the country, more food than even I can eat and incredible performances in the evening. Definitely check this out if your in Udaipur in December 2014!