So, I'm very interested in the discussion started by Bird Stuff about using Google Trends to measure an activity's popularity. Have you checked out Google Trends? It's a way to track and search out how popular things are down to the region. Birding is not nearly as popular as hunting and especially fishing. I'm not sure if this means birders are deluding themselves about how many people are interested or if it just can't be quantified that way?
I did a comparative search for the ivory-billed woodpecker with birds like cardinals, hawks, owls, etc--even gull registered higher than ivory-billed woodpecker. Apparently, ivory-bills are not nearly that fascinating to the world. Hm.