I've just joined GetWatchers and it's pretty cool.  When you join, you can submit your artwork to their gallery, then use their Art Viewer to see a slideshow of other members' works.  For every one you view, you get one credit.  Those credits allow others to see your art in the Viewer as well.

It says that if you view for 30 minutes, you'll have approximately 200 views of your art!  Also, if you link to the group, and invite new members, you get 40% of the new members' credits, as well  I'm excited!!

[link] Check it out