Google's Birthday?

I've been getting a lot of notices about today being Google's birthday. At first I ignored them, because Google's birthday is on September 27th, which I recall because it is also my birthday. But I keep seeing birthday notices everywhere, so I "Googled" it. (In other news, "Google" is the only word I've ever put into the Google search field that did not have a Wikipedia entry on the first page of results.) About.com has this to say:

Google's birthday has shifted around over the years, but it currently is celebrated on September 27th. The exact year of Google's "birth" depends on how you measure it.

The Web domain www.google.com was registered in 1997, but Google officially opened for business in September of 1988.

And Wikipedia says:

The domain name for Google was registered on September 15, 1997,[41] and the company was incorporated on September 4, 1998.

The Google blog doesn't say anything, because there's no entry for today -yet. Some big British newspapers: The Independent, The Guardian, and the Daily Mail, all have congratulatory stories on Google's 15th birthday. But the most telling clue is the search page itself, which has no Google Doodle for today, meaning they probably plan to celebrate on another day. Maybe on my birthday!

(Image: last year's Google Birthday Doodle)