Could today's doodle hint at HTML5 Google?

UPDATE 08/09/10: The bouncing balls are gone. Now we've got grey letter that light up when you type - is Google looking to announce the wider launch of its streaming search?

It's unlikely you'll have missed Google's trippy-looking bouncing ball doodle for the day - but could it be a clue to a major announcement due tomorrow?

The animation has been programmed, says tech blog Pocket Lint, using HTML5. And as anyone who has tried to click the graphic will have discovered, rather than yielding some sort of explanation in the usual manner of the site's commemorative graphic, today's colourful balls flee from the mouse pointer as it approaches.

New web language HTML5 has been championed by Apple after the company banned Adobe's Flash from any of its products, sparking a feud over the future of web-based video standards. Ironically, today's offering refuses to work in Apple's homespun browser Safari.

HTML5 is credited by supporters with breaking down the barrier between web-based content and the desktop, allowing users to drag and drop elements from their browser window to their computer just as they would between folders.

Google used commemorate its birthday on September 7th, but has since moved celebrations to the 27th in 2005, to fit in with an announcement on the site's search index.

Google itself has said of the change: "The exact date when we celebrate our birthday has moved around over the years, depending on when people feel like having cake."

So what's the story with the graphic? According to the UK's Daily Telegraph, sources at Google are remaining resolutely tight-lipped.

Others, such as Pocket Lint, have suggested the graphic heralds a big announcement at an event to be held by the company in San Francisco tomorrow.

Invitations have been sent out to journalists over the last few days, reading: "We invite you to join us on Wednesday, September 8, to share our latest technological innovation and to get an inside look at the evolution of Google search."

The graphic could suggest an announcement is due concerning HTML5 implementation by the search giant. Other sources predict a look at Google Goggles, the company's forthcoming image-based search feature.

We'll just have to wait and see.