As for your questions:
- Do you see a use for this in your daily life? If not, is there additional/different content that will get you into using something like this? Yes, but it only pulled up one concert for my area (Little Rock/Jonas Brothers, yay), and I know we've got more going on than that. So you need a little more depth on your tails before I'd start using. Probably not a problem for users in bigger markets, but still.
- What sort of events are you most interested in (I understand HN might not be the representative audience, but its still quite a big one in itself)? The only type of events I can think of off the top of my head that I'd want to search would be concerts, shows at the theater (which I frequently miss out on b/c I never think to check), and local MMA fights.
- How do you go about planning to attend events with friends (phone/IM/text/emails/facebook)? My main group of friends is stuck in the email chain loop for organizing things.
- What time frame of event search would you be interested in? This evening? Weekend? Next month? Depends. Seems like this should be a third search parameter.
Also, I know we all hate IE as web developers, but if you don't want to throw away 60-70% of your potential traffic, you MUST support IE.
Overall, nice work.
Edit: Geez, how does a guy do a single line break in a post?