You need my "ancestry" for me to register. Is that user driven or do you just get more money for the db with ethnicity info, it has a "*" in the sign up page; http://digidorm.com/user/register .

The page loaded very slowly for me, YSlow report 5000 DOM objects on the registration page ??

Asking for a matriculation or student ID might reduce signons from non-students even if you can't verify them - once you have some you'll be able to create a pattern.

I was impressed you had an apparently comprehensive list of uni's - I thought Open Uni might catch you out - you should play this up "every Uni" and emphasise the global nature of the site.

Your CC link at the bottom strongly suggests a CC-license but none is made clear; this suggest to me you're trying to con me in some way.

Advertising being the top of a main menu listing (Services) suggests that the point of the site is to make you money with targetted ads. That may be true but you perhaps want to be more subtle about it.

Edit: the logo ain't retro it's horribly 80s corporate looking. The colour scheme is bland. Align that search box or I'll go mad! The guy in the suit is not a good try at a hero shot - hot coeds is the standard. What are you doing to avoid astroturfing?

Just my initial thoughts from a couple of minutes contact.