Just tried it. Really cool. I have one question though. The option to right click and "Export HTML/CSS" only exports the current selected widget and not the entire grid/layout. That would be awesome if possible :)
We realize that it's a difficult problem to create good markup but that doesn't mean we can't help. So we felt the best tradeoff was to give the CSS properties used so you can spend less time with the eyedropper tool.
There is an option to export the full page but we think it's best for quick prototypes.
Easel aims to be a design tool, I think, to help you in coding and designing sites, but won't do all of the former for you.