This market place is very well built and has really great features. It has supposedly been around for 8 months and it feels stable.
TorEscrow has a simple ranking system for vendors that indicate which vendors have more experience, and rewards the more experienced vendors with cheaper commission rates.
The site has PGP password recovery, a web of trust invite system that promote inviting good people over spamming. They moderate the market regularly and automatically remove listings that are stale after two weeks. Making it have less listings but what is there is active. Vendors can save shipping options and apply them to their listings.
Most importantly their help desk support staff is great, they responded to me both times within 12 hours and the minor suggestions I made were put into place within days. I have heard great things about their support from others too.
Currently vendor accounts are free
I like TorEscrow too :) Few listing though