I am trying new microstock site: Cutcaster. I uploaded couple hundred of pictures. Upload process is quite easy. This is one of the new wave of site which start with pretty usable UI. Aa interesting feature of Cutcaster is dynamic pricing algorithm which can vary the prices of your images or video to increase sales. Price is set by the photographer, then all calculations are based on this default pricing. This site uses up to five categories per photo but it's not mandatory to set them which is great plus cause I hate site required categories. Another feature, that I cannot really verify cause I do not have any sales, is that buyers can also bid on your work, and you can choose to reject, accept or respond with a counter bid to their price offers. I do not know I would have time for haggling, especially that I expect bids would ask for lower price :-)
No complains on workflow but site is still in beta so from time to time your submissions may fail. Usually it would show some message:
The Beta site, by definition is work in progress, so I guess most of the problems will go away with official release.