Since launching my Wind History map about three months ago, the site has had about 6000–9000 pageviews, or about 100 visits a day. Not exactly blockbuster, but I never expected the site to be a big hit. It's as much a tech demo of advanced map datavis techniques as anything and at that it's a success.
The most popular airports are San Carlos and Santa Fe, no doubt because I use them as examples. Folks are also notably interested in Snyder, TX (from an AOPA discussion); Camp Bondsteel (in Kosovo) and the NAS Whidbey Island and neighboring Oak Harbor in Washington.
The nice thing about a static site like this is it takes no maintenance. But I'm playing with some new features now. Geolocation API to move the map to where you are, fancier wind rose diagrams, and static HTML for dumb ol' Googlebot.