Google statement regarding the Gmail outage yesterday:

"The problem with Gmail should be resolved. We apologize for the inconvenience and thank you for your patience and continued support. Please rest assured that system reliability is a top priority at Google, and we are making continuous improvements to make our systems better.
As of 1600 Pacific Time, Gmail message delivery and attachment download is functioning normally for all users. We apologize for the duration of today's event; we're aware that prompt email delivery is an important part of the Gmail experience, and today's experience fell far short of our standards. We have analyzed the data on user impact and are providing a preliminary assessment of what occurred:

Between 0554 and 1530 Pacific Time today, 29.1% of messages received by Gmail users were delayed. The average (median) delay was just 2.6 seconds, but some mail was more severely delayed. However, this issue did not affect users' access to the Gmail page or other functionality."