We—Eevee, epii, and others—are building an art site, because the market has stagnated and we think we're clever.
We value transparency, streamlined UI, organization, and above all supporting the artists before anyone else.
It's not really ready for primetime yet, but you can see the site so far if you'd like.
There's a tumblr with intermittent news posted, a (somewhat outdated) planning document, and an IRC channel.
The backend, "floof", is written in Python, runs atop Pyramid, and stores data in PostgreSQL and MogileFS.
Code, issue tracking, and various documentation live on GitHub. Most discussion happens in the development IRC channel.