There are reports across the web that Google Analytics has gone down for about 30 minutes.
First reports started coming in at about 5:30am (EST). By around 6am (EST) people started confirming that they can log into Google Analytics.
People were noticing 404, page not found, errors when trying to access reports. Many were completely unable to login to see their reports.
Nikos Kapsomenakis posted a screen capture of the issue.
All seems to be clear now.
Forum discussion at DigitalPoint Forums and Google Groups.