In doing some search engine optimization (SEO) homework before the launch of MB's hip new website (shh!) I was checking out our backlinks to see if we had any especially valuable ones that pointed to specific URL that would soon be out of date.
The most valuable SEO back links were from websites we'd helped clients to build, and which had then gone on to the top of the Google search results for their own keywords (keywords which aren't that valuable to us). Clients who've just had their websites launched in the last week or so obviously didn't provide as valuable a back link.
It just goes to show that doing good work for clients pays off for you too. It's also why I'm convinced that in the long run, proper SEO will be synonymous with high web standards.