OK, so calling it a "con" may be more than a bit of a stretch, but OTOH Eurofurence also started out with 19 folks meeting on a farm in the middle of nowhere. (Speaking of Eurofurence, the EuroAvatar website reminds me of the Eurofurence website quite a bit, structurally speaking; I wonder if they got inspiration there, or whether there's a significant overlap between the organizers/attendees of this one and furries.)
EuroAvatar 3 will also feature Paul Frommer, BTW, the communications professor at University of Southern California who designed the Na'vi language for Avatar and who continues to work on it (naviteri_rss on LJ, for those interested). The last two years, he's been there by way of Skype; this year he'll attend in person.
The whole con seems to have a strong focus on the Na'vi language, anyway. Which makes sense; it's an easy and natural entrypoint for getting more involved with Avatar and for professing your love for the film. If I'd actually ever tried to learn Na'vi (I read Paul's writings on it and find it fascinating, but I've never made any serious attempt), I'd be tempted to go, too. To all of you who do — have a wonderful time!
(Mmm, I do wonder just how long it'll be until we'll have an organized Na'vi fandom that rivals furry fandom in size and scope. :))