I took the plunge yesterday and opened an Art Fire Kiosk (Click the title to this post to see it). I am in the process of also listing my items there. They have an import function, but unfortunately if you do that, your item doesn't get listed on the front page when you do a new listing. That generates a lot of views, so I am having to hunt down the photos on my computer and then rewrite the listings for Art Fire.
Please swing by my shop and say howdy! Any followers, please feel free to leave links to your shops in the comments!