Do board rankings matter at all? I mean- if you ranked #1 would you get a lot more visitors?
I think boardtracker is a great resource to get a nice broad view of things.
I'm registered on probably - dunno...10 boards. I post almost exclusively here...for better or worse.
It's pretty hard to judge a community based on numbers.
You can come up with a formula of some sort, but that's just a snapshot of an aspect of web traffic.
The community is all about the peeps, the posts and the PM's when all is said and done.