I've got you by a couple weeks :) We went live with a site on Aug 2nd. In Yahoo on the 7th. And now #2 for main KW. But I did have a link to the site on a PR8 site starting July 25th. So that might have helped just a bit, but congrads on the #1.... :)
But, no, not a record. Just a bit over four weeks, in fact, isn't uncommon. Get a site with a couple of backwards links in right now, today, as the update completes and you'll probably be crawled in the next couple of days and likely be listed as of the September update.