There will be GrabPERF downtime on May 29-30 2009 as Technorati completes its colocation relocation process. [here] There is no set time for the outage or its length, as the machines have to be physically relocated to the new datacenter, and then integrated into the new network configuration.
I will be contacting the agent locations in the next few hours to update them on this maintenance.
UPDATE: GrabPERF returned to service as of 23:40 GMT on May 30 2009. Thank you for your patience.