While there appear to be a number of sites operating in this space (documented some here: http://web.onassar.com/blog/2012/11/19/web-based-screenshot-...), this looks simple and straight-forward. While the cost is prohibitive for me since there are free alternatives (http://immediatenet.com/), it's great to see more competition in this space.

For what it's worth, I'm using it on my site http://imnosy.com