Google has launched a new site called AgencyLand. The site is an answer to requests from advertising agencies for resources to help them manage their clients' accounts. Originally launched into a closed, private beta in March 2009, AgencyLand is now available by invitation to agencies and third parties in the United States and Canada.
You can request an invitation at the homepage of AgencyLand.
In the meantime, here's a video featuring advertisers saying why AgencyLand is Awesome Town.