Google doodle mystery continues

Google has launched a second Google doodle this week with no explanation and no apparent connected special occasion or anniversary.

Wednesday's doodle shows a greyed-out version of the normal logo that then changes to the Google colours when a term is typed in to the search bar.

It is the second design in as many days without an official explanation and has fuelled rumours about what Google is planning to announce at an official press conference in San Francisco on Wednesday.

On Tuesday Google replaced its logo with an interactive doodle with balloons flying around the page when the mouse was moved.

Normally when you hover over Google doodles it will tell you what the new design is in honour of but neither Wednesday's or Tuesday's doodles do.

Both only appear to work on the UK and German versions of the search engine - not Google.com - and only work in certain browsers.

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Speculation about the doodles and Google's impending announcement include a HTML5 tie-in or Google launching visual search, after buying the technology in the form of Like.com in August.

Rumours also suggested that Tuesday's doodle may have been to celebrate the search engine's birthday, but the second one on Wednesday may discredit this theory.

It has also been claimed the doodles may simply be a way of encouraging people to upgrade their browsers.

But a Google spokeswoman upheld the mystery of the doodles and alluded to a big announcement when she told Web User on Tuesday: "Today's doodle is fast, fun and interactive, just the way we think search should be."

"So watch this space," she added, refusing to comment further.