I think the event would be small for a first run. Even if people would fly over/travel for something more significant, I don't think we can jump in to some kind of convention-size event right away because of the organisational effort involved, and possibly risk (we don't know if this type of event works yet).
Also only 16 yes votes so far, and I guess about half of those would be busy/unavailable for any particular date we pick... so it could be pretty small! Still, got to start somewhere, and maybe we can figure out a way to grow it. Running it during Eurogamer sounds like a good idea too (26-29 sept) and if we arrange something I'll try to put it together with several week's notice so everyone can book themselves.
Not sure a live stream would work for a simple pub meet, since people would just be milling around talking to random people I guess, not much to watch. However if we arranged some demos or talks maybe that would be interesting to others?
Setting up a meetup forum is a nice idea, I'll see if we can put something together.