As someone who makes a living selling layer styles[1], I have to say this is very cool, but also slightly worrying ;) I've been trying to figure out how long the market for Photoshop addons will last, as CSS and other technologies advance to the point where everything can be done in the browser. Clearly, we're getting closer.
You'd be surprised. I know photographers that make a decent living selling PS actions, templates and Lightroom presets. Usually more than they make actually taking pictures.
The glass effects look good. I noticed you are using fastspring which I have been considering as a payment processor, Have you had any issues with them? Also can you tell me how well does it handle digital downloads? The way it releases the download to the paid customer, or is it something you handle yourself? Thanks for any advice.
[1] http://photoshoplayerstyles.com/