I think its a cool project. I thought its interesting as they will be the main competitors to ShadyBay/ShadowBay and they offer interesting insight into how to solve some of the problems of a decentralized marketplace. In the end Shadow may have a competitive advantage because of the extra privacy and anonymity it offers buyers and sellers, but Shadow also has to compete against Bitcoin's network effect.
Also wondering if Sbay will have multi-signature involved at some point. That seems like an important piece of the puzzle.
OpenBazaar is a very interesting project indeed!
One thing the team (working on Shadow Market) may need to consider as they prepare to release this to the public is how much liability they want to take on by hosting the decentralized marketplace. Being the operator of a point of sale destination that potentially has illegal paraphernalia being sold on it now has a legal precedence in the eyes of at least one government. https://www.cryptocoinsnews.com/ross-ulbricht-convicted-running-silk-road/
Also, I assume they are implementing a multi-sig / trustless escrow system.