Dropbox are in an interesting position- they're practically a "cloud utility". Like if ConEd invited me to "discover the possibilities when you use electricity", I don't really know what I'd get out of a Dropbox conference. It does file syncing. They have an API that allows you to sync files. Right. Either the topics would be so specific that they'd all repeat each other, or they'd be so broad that they would only tangentially touch on what Dropbox does.
That said, there isn't an agenda so i can't find out.