Keyword Heavy File Extensions

hi, Marco, how are you?

if you search google for the phrase test cfm you'll see that quite a few pages turn up with cfm extensions. while some of those include the phrase 'cfm' on the page, many do not. there are two potential reasons for that:

1. google is using the extension as a parameter in search ranking
2. other pages are linking to those pages using the url as the link text (link text is a ranking factor)
   

a quick look at the backlinks for one of those results in yahoo - "cdrp.net/test.cfm" - doesn't seem to find any pages linking to it using the URL as link text & a search on google for that exact phrase returns only the page itself.

so, in short, yes, file extension does seem to be processed.

even if it weren't, using a relevant file extension in your URLs could still benefit you in two ways:

1. some of your inbound links will probably use your URL as link text & thus will contain your file extension & give you a little more equity for that keyword
   
2. when your site pops up in the SERPs against a keyword you're using in your file extension, that portion of the URL will be bolded, slightly improving your chance of clickthrough

reasons why you might not do it:

1. it looks quite 'spammy'
2. if you're using a different file extension on every page, that can look odd to visitors (for example, if you're doing this for a bank, someone receiving an email containing the URL 'www.bank.com/mortgage.loans' may think 'that address looks a bit dodgy' & you potentially lose a click & some trust)
   
3. why not just include the keyword in the filename or directory name?

hope that's of some help.

daniel