Just a great place... although I'm a huge Warhol fan so of course I'm a bit biased. There are always new exhibits going on here, and they also have great indie concerts from time to time.
I've also heard that band members often stop here in the afternoon when they are passing through town to play a concert, so it can be a good celebrity spotting site. My favorite memory here is sharing an elevator with John Waters during the opening of his exhibit.