This afternoon, in the Bellavista neighborhood of Santiago de Chile, I saw a guy wearing a "Seattle Central Business District" t-shirt. I'm pretty sure this guy had not much if any idea what his shirt meant. But that isn't the point. Should he ever want to explore the meaning of his attire, and should FT have a Seattle forum at the time (and should he have happened to learn English in the meantime, or at least use a good translation site), he might actually want to visit Seattle.
This, I fear, is the strongest argument I currently have for a Seattle forum, but it is timely, and really points to how someone doing a web search for Seattle travel might me a lot more likely to find it on FT with a Seattle forum than without.