Chicago is one of the cities I'd love to go back and explore with more time, so I think the TFCon is likely to be there each year if it becomes an annual event... as their Canadian one has always been in the state of Ontario, and the last four have been in the one city (for convenience and streamlining I guess).
I'll keep an eye on it for next year though, unless BotCon is in Chicago next year, then it would be a bit much visiting that city twice in a year.