In a rare instance, WordPress.com was offline for almost two hours on Thursday February 18th, 2010 (Pacific Time). The team at WordPress still looking at the cause of the outage so to prevent it from happening again.
The outage happened when I was updating WordPress Stats plugin for the self-install WordPress Blogs that I am managing/maintaining. Based on this one information, could the outage involved WordPress API server or the Stats server?
Since I don’t really have access to WordPress.com core servers, I wouldn’t really know what was really going on. It’s just a hunch.