Yesterday many Gmail users have experienced problems in accessing their account. After several hours of outage the problem has been fixed and Google made a public apology for the issue.
According to Google the issue was caused by a temporary outage in our contacts system that was preventing Gmail from loading properly. Google promised that it will conduct a full review of what went wrong and it will update its internal systems and procedures accordingly.
Google’s official apology: http://gmailblog.blogspot.com/2008/08/we-feel-your-pain-and-were-sorry.html.