In a surprise move, Yahoo! has appointed Google’s leading executive Marissa Mayer as its chief executive.

Yahoo! has almost gone off the face of the planet in recent years following the increased competition from search rivals Google, as well as the emergence of social platforms Facebook and Twitter.

The company’s news service attracts good numbers of traffic, but other products supplied by Yahoo!, including their search engine and email have lost a lot of users over the years.  Their revenue from paid search advertising has also declined.

Marissa Mayer will become Yahoo!’s third CEO in less than a year when she officially steps into her job when the sun comes out in California this morning.

In September 2011, then-CEO Carol Bartz was relieved of her duties via a phone call after two-and-a-half years in her role.  Her replacement, Scott Thompson stepped down in May this year after claims he put a Bachelor's degree in computer science on his CV which he did not have.

Interim chief exec Ross Levinsohn had been widely expected to take the job before Monday’s announcement.  Mr Levinsohn has yet to Tweet a reaction.

In Yahoo!’s released statement, Ms Mayer said she was “honoured and delighted to lead Yahoo! [sic]”, and later Tweeted the following:

The new Yahoo! CEO then tweeted to announce she is expecting her first child on 7 October:

Ironically, Marissa Mayer hasn’t updated her Google+ account which still says she works at Google:

Marissa Mayer originally joined Google back in 1999 as the company’s first female engineer and the growing company’s 20^th employee.  A former student of computer science at Stanford University, she worked on the Google search engine as well as their popular, plain home page.

In recent times, Ms Mayer has been in charge of Google’s location and mapping services, including Google Maps, Local, Street View and Earth.

Prior to joining the Yahoo! board, Marissa Mayer also servces on the boards of Walmart, the San Francisco Museum of Modern Art, the San Francisco and New York Ballets.