I'm by no means an expert but in addition to the number of links to a site, 'Keywords' are very important. They are contained in things called Meta Tags in the code that produces the page. The surfer doesn't see these but the search engines and directories do and their relevance to the headings and content of the pages are important factors.
CA's homepage keywords are PHP, MySQL, bulletin, board, free, open, source, smf, simple, machines, forum
They don't even mention Le Mans! They look like they were put there by the authors of the forum software and haven't been customised for CA.
This isn't surprising as forums are usually embedded in a site that has ordinary webpages; index, about us, contact etc.
That's certainly why Beermountain will rank higher than CA. And, hey, as a regular contributor to BM (and the CA Guide) it's a bit insulting to hear that it's only about stacking stubbies. We've all got a common link in Le Mans and I know that there are many people who are, like me, members of both communities.
Moan over - if Le Mans is included in the keywords the rankings will improve.