I've been covering the intersection between event and social networking arena here.

Upcoming.org started as a way for regular people to enter events and share them with their friends. They are still all about that, but they've made some changes to keep up with the Jones's. In this case, to keep up with eventful and zvents. Eventful has been making deals with other event companies to get access to their data. I am not sure if they are crawling and indexing events from other sites? I know they are getting feeds from other sites. Zvents has been making deals with media companies to help them manage community event listings. Both are quick ways of getting a lot of event data.

Not as fast as Yahoo's search engine, though. Upcoming.org just leveraged the crawler, indexing, algorithmic prowess of Yahoo! search to bump their event database up a HUGE notch.

They also integrated with Flickr photos so people can view their flickr photos at upcoming.org. About time for that one.

More changes are detailed at Upcoming.org. I'd say they just reclaimed their title for the best social event website and event database.