I've been looking for something like this. Lately it seems that we're doing more and more wireframing at my work, and having to pull out illustrator, and then deal with large files and passing them all around into SVN and whatnot has gotten to be a huge pain.

I'm going to check this out.

I'm also curious how their flowchart handing is. I've still never found a decent flowcharting program made for coders. It was getting to the point where I was actually considering making one to fill my need...