Saw them pitch at 500 Startups Demo Day. As an event organizer, the concept of maintaining the relationship with attendees over multiple events really appeals to me.
Obviously many competitors, including old-timer Eventbrite and EventJoy (also posted to PH today).
This is a hot space. At first glance, they seem to be going after the "power user" with advanced analytics, some level of a CRM, etc.
If you haven't already, check this out @allnick.
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