Whilst I'd like to say that you're too late to suggest somewhere as they've chosen a place, I can't.
However, the poll on the front page suggested that if RuneFest or a similar affair happened in America then players would want this event in New York. Unfortunately with the USA being so big, players are going to travel come what may, so I'm not sure that it makes a difference - come hell or high water you'll find a way to get there.
I know that it's easier to have it closer to you, we've had the same troubles with UK meetups. I'm sure you'll get to RuneFest even if it's not where you live.