I think it's a nice, useful app. This could be a really cool facebook app as facebook's event planning doesn't allow for gathering individual's preferences. I'd use it on facebook, to be honest.
I really like how you convey the purpose of your site by showing users the steps, and the steps you outline makes me understand the value of your service. My only question is about how the responses are stored, as there isn't any sort of log in screen, unless it generates a unique url (I haven't created a gutmeet). The site could be redesigned in a much more modern and fresh look. Please get rid of that font for the logo :P. Maybe a better name could serve well. Gutmeet makes me think of someone eating a chunk of my intestines.
Congrats, though. Really consider a facebook app. I think something like your service, with more features, can turn into a full fledged event planning network that supplements the crap facebook provides.
