At the When 2.0 conference, where I'd officially announced our universal events submission feature, Ethan Stock had stopped by to congratulate EVDB on shipping such a feature. "We'd thought about doing that," he said.
Well, we shipped it. And then Yahoo/Upcoming complained, and we temporarily disabled support for automatically submitting events to Upcoming.org, at least until they could make some changes on their end and we could make some changes on our end (happily, work is progressing very well on that front and we hope to have Upcoming.org integration re-enabled soon).
And then the other day I got an email from Ethan asking us to voluntarily disable auto-submit to Zvents, at least until they could make some changes on their end, and we could make some changes on our end. (I sense a pattern developing.) And so, we complied, and for the moment, the Zvents checkbox is disabled as well as Upcoming. We hope to hear from Zvents soon with news that they've made the necessary changes on their end (we're already underway with changes on our end) so that the auto-submit feature works again and everyone's happy.
We continue to offer Auto-Submit to ping Technorati and Ping-o-Matic, as well as to submit a bookmark to Del.icio.us/events. Please note: if you intend to auto-submit an event to Del.icio.us, PLEASE be sure that you've tagged the event well. There's nothing worse, indeed, I would consider it a "web sin" if there is such a thing, to submit a bookmark to del.icio.us that does not have tags for people to find it.
As a general rule, I find that any event one adds to Eventful should have at least 5 good, solid tags that describe what this event is. Probably two or three tags just to describe what type of event this is, and some then to describe the people or topics or other things that make this event particularly notable.
Finally, keep sending us suggestions on where you'd like us to also auto-submit events. We're talking to a number of places and expect to have more places to submit to soon!