Perhaps the invited party can comment to say they're going, though it'd have to be mentioned that this action is expected of the user. Even if it's just their n

Perhaps the invited party can comment to say they're going, though it'd have to be mentioned that this action is expected of the user. Even if it's just their name as a comment...but it starts to lose value if no one knows who that person is (only among friends would it make sense). If not just among friends, there might be a field for a link to one's preferred social network profile, for verification (by the organizer). I also dislike the collaborative feature because, as another HNer mentioned, it isn't too conducive to a smooth meetup process. If someone selects 'attending', is then asked for their first name and then, optionally, can add a one-time pic of themselves (rendered slightly larger than a thumbnail), that'd help too. The only issue with that is then you'd obviously have to deal with logins, passwords, etc.