Google quickly fixed the bug and has contacted everyone who was affected by email.
Then on Tuesday, Google mail - or Gmail - went down again for about 30 minutes before being fixed. Although it affected only a "small number" of the 113 million Gmail users, the problem could lock some users out of their accounts for more than 24 hours.
While the problems have not caused Google to suffer financially, the increasing number of glitches it (and others) are having is increasing the awareness of the risks of software as a service.
Well, at least Google is open about its problems (see the Google status board here).