Oops! Here's proof it can happen to the best of us ... and that even sticklers don't always notice. I looked at this logo many times on Feb. 14th and never once noticed the spelling error in Google's logo .... someone else had to point it out to me!
It reminds me of studies I've seen where people are given trick sentences to read. The results always show how often our brains automatically "fill in" gaps or "overlook" things like two two repetitions of the same word in a sentence.
I think Seth Godin was the first blogger to post about the Google error.

Hi, Gord,
I should have been more clear - this aberration occurred on one day only: Feb. 14, 2007 (Valentine's Day) - Google often customizes its logo based on special dates. For example, this year for Chinese New Year the logo featured a pig and some Chinese characters.
Posted by: Maria Ford | March 08, 2007 at 02:47 PM
Hmmm! I'm curious as to the geographic location of Seth Godin who initially blogged this dilly. I live in Canada and when I manually enter "Google.COM" in my browser address bar, I am re-directed to "Google.CA'. Both the latter address and the one for "Google Scholar" (now in beta) do NOT display this aberration.
Posted by: Gord Richardson | March 08, 2007 at 01:46 PM