Same issue for me-- I couldn't readily determine whether this was an open source project, like MediaWiki, or a hosted service that I'm going to pay to use. A lot of the corporate and pricing info I look for was under a different URL, EdGenius, which adds to the confusion.

The signup button should lead to a page explaining exactly what I'm signing up for, rather than the existing lightbox, which has an unattractive little form offering no details.

I like the overall presentation feel on the homepage; you just need to provide more direction for the new user.