San Francisco-based Attendio, which seems like a quicker, much more official version of Upcoming.org, came to my attention recently. Currently only supported in selected regions in the U.S., Attendio helps you track and find local event information in the areas you’re interested in.
How It Works
While Attendio may strike as similar to Upcoming, Attendio is solely an events discovery service — as in it’s focused more on the personalized what-the-user-should-attend aspect as opposed to ‘hey, we’re having a massive party, who can come?’. It currently supports about 12 regions, though there is an ‘Other’ option for others to poke at. The homepage provides three basic steps, allowing you to pick a category, a location, and interest 
(i.e. concert or venue:park). The system then spits out a list of events that match the information provided, from which the user can decide to ‘pick,’ and signup, indicating that they might be attending the event.
Attendio also provides a calendar to filter through, and a list of users who might be attending events from the matches. Additionally, users can build a personal calendar tracking their person selection of events and create a list of interests, a ‘watchlist’ of sorts. Also available, something I love, is the ability to lookup and search through events from cell phones via SMS, e.g. by sending “94109 March 4 rock” to ATTEND (288363). In all, the focus is to best match and filter through the kind of events a user might be interested in attending, also incorporating some social networking and calendaring features along the way.
Opinion
If I were living in one of the supported areas (or the U.S. at least!), I wouldn’t look further than Attendio and Upcoming for my social event life. Attendio is an impressive product, and while it may seem as trying to serve too many users by letting any type of a user search for any type of an event, I think that’s the whole point behind the service and if it can find that open-minded type of an audience and build up a strong user base of event-goers, it has a chance of sticking around — just like its partner-in-crime Upcoming.
