While I’m not sure if I agree with the actual metrics themselves (number of layouts delivered seems sort of meaningless and easy to inflate, as Scott Berkun points out in the discussion thread), but I’m interested in the basic idea of regularly measuring yourself as a group (or as a team of one, natch), and gauging your own progress against that.
Even just asking your clients in a regular and structured way about how happy they are with your contribution and how much they think you’ve improved their product and/or process would be kind of groovy.