Arisia registration figures are pointing to a con of around 2900 or perhaps 3000 people. This is squarely in the middle of a strange no-man's land: there's very little data about how conventions of this size work. Boskone went directly from a 2700 person con in the Park Plaza in 1984 -- something the dynamics of which Arisia understands intimately -- to the largest SF convention in the world, and already too big for its new and bigger hotel, in a single year (1985). Minicon likewise skipped over 3000 as an attendance figure, and found (as Boskone did) that a 3300 person con is very different to run from a 2000-2500 person one.
I'm sure everyone will fit in our enormous new hotel, but I'm really quite curious to find out which things will be the same and which will be different at that number, because almost no one has done it before.
And I'm glad that we still have a membership cap, even if it's higher than it was before.