Please review Utilium.com – a web app for sharing learning materials
mdolon: In my opinion, the 37signals style of displaying a product works so well is because of amount of information readily available with such little effort.  Your design looks pretty attractive already and is in a similar sales letter type layout - consider adding a tour with large screenshots.  It may also benefit you to mimic the style of their pricing page with each plan laid out, even if the primary one is free.  There's a sense of mental relief if the customer knows what he/she is getting into at a quick glance and that pricing chart helps a ton in providing that.