As Massimo points out above, the team at tenthrow uses web2py for tenthrow.com
We did most of our development work during 2009. Our stack uses cherokee, web2py, postgresql, and amazon s3. We had done many python web implementations prior to this on a variety of frameworks and backends. To say that we simply could not have done tenthrow so quickly and easily without web2py is an understatement. It's the best kept secret in web development.