Xbox chief Don Mattrick has left Microsoft to replace the CEO of social gaming company Zynga.

Mattrick joined Microsoft in 2007, heading up its Xbox gaming and entertainment business. In the past six years the console has increased its user base from about 10 million to more than 76 million, with the company widely seen as having come out of this generation of hardcore gaming consoles ahead of Sony's PlayStation 3.

But with the next-generation Xbox One and PS4 on the horizon, Mattrick's gaming division has been seen to have stumbled.

The Xbox One launch was marred by criticism first of its complex rights management policies, and then of a sudden U-turn which made it easier to share games - but pulled back on intriguing new online features.

And with the console now set to launch in November, Mattrick appears to have had a better offer.

Effective immediately he will replace Mark Pincus as the CEO of Zynga, the company famed for games included Words With Friends and Farmville which has struggled in recent years to hold onto its core user game and expand revenue on mobile devices.

The result has been a declining share price since its $1billion IPO in 2011, and the loss of more than 20% of its staff in the last twelve months.

But in the immediate aftermath of the announcement on Monday shares in the company shot up, as the market welcomed the change in direction.

In an email to the company, Pincus introduced Mattrick as as "unique" games industry "innovator".

Pincus will stay on at the company as chairman and chief product officer.

He said:

"Over the last few months I've spent a lot of time thinking about all that we have achieved together as a company. We have pioneered social gaming and helped make Play a core part of millions of people's lives. But Zynga has so much more potential ahead, the opportunity to be an Internet Treasure and deliver on our mission of connecting the world through games.

As I reflect on the past six years, I realize that I've had the greatest impact working as an entrepreneur with product teams, developing games that could entertain and connect millions.

I've always said to Bing and our Board that if I could find someone who could do a better job as our CEO I'd do all I could to recruit and bring that person in. I'm confident that Don is that leader."

While Mattrick followed up the email with his own note to employees:

"I joined Zynga because I believe that Mark's pioneering vision and mission to connect the world through games is just getting started. As Mark was recruiting me to come here, I was impressed by his creativity, drive and the clarity in which he sees the future of games and entertainment as a core consumer experience.

For the last 30 years, I've been fortunate to work with smart people on exciting projects. I've managed over 100 platform transitions and I've never lost my love for seeing products as creative experiences that bring people together...

Zynga is a great business that has yet to realize its full potential. I'm really proud to partner with a product focused founder like Mark and work with the executive team to grow the DNA of the company and lead this transition."

Meanwhile Microsoft CEO Steve Ballmer said that Mattrick would not be immediately replaced, and that in the run-up to the Xbox One launch he would take over responsibility for the division.

Ballmer said:

"Thank you, Don, for setting us on a path to completely redefine the entertainment industry. The strong leadership team at IEB and their teams are well positioned to deliver the next-generation entertainment console, as well as transformative entertainment experiences, long into the future."
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  • This product image released by Microsoft shows the new Xbox One entertainment console that will go on sale later this year. Microsoft is seeking to stay ahead of rivals in announcing that new content that can be downloaded for the popular "Call of Duty" game will launch first on Xbox One. Microsoft says more games will be shown at next month's E3 video game conference in Los Angeles. (AP Photo/Microsoft)

  • Microsoft Corp.'s next-generation Xbox One entertainment and gaming console system is shown on stage Tuesday, May 21, 2013, at an event in Redmond, Wash. It's been eight years since the launch of the Xbox 360. The original Xbox debuted in 2001, and its high-definition successor premiered in 2005. (AP Photo/Ted S. Warren)

  • Photographers crowd around Microsoft Corp.'s next-generation Xbox One entertainment and gaming console system after it was officially revealed, Tuesday, May 21, 2013, at an event in Redmond, Wash. (AP Photo/Ted S. Warren)

  • A controller for Microsoft Corp.'s Xbox One entertainment and gaming console system is on display after its unveiling Tuesday, May 21, 2013, at an event in Redmond, Wash. The Xbox One, a next-generation entertainment console that promises to be the one system households will need for games, television, movies and other entertainment, will go on sale later this year. (AP Photo/Ted S. Warren)

  • This Tuesday, May 21, 2013 photo shows a rear view of Microsoft Corp.'s next-generation Xbox One entertainment and gaming console, on display at an event in Redmond, Wash. The Xbox One, a next-generation entertainment console that promises to be the one system households will need for games, television, movies and other entertainment, will go on sale later this year. (AP Photo/Ted S. Warren)

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    The Kinect motion-sensing device for Microsoft Corp.'s Xbox One entertainment and gaming console system is on display Tuesday, May 21, 2013, at an event in Redmond, Wash. The Xbox One, a next-generation entertainment console that promises to be the one system households will need for games, television, movies and other entertainment, will go on sale later this year. (AP Photo/Ted S. Warren)

  • The new controller for Microsoft's next-generation Xbox One entertainment and gaming console system is shown front and center with older-generation controllers behind it, Tuesday, May 21, 2013, in Redmond, Wash. (AP Photo/Ted S. Warren)

  • IMAGE DISTRIBUTED FOR MICROSOFT - Press photograph Xbox One following the Xbox One reveal event on Tuesday, May 21, 2013, in Redmond, Wash. (Photo by KAREN DUCEY/Invision for Microsoft/AP Images)

  • IMAGE DISTRIBUTED FOR MICROSOFT - Don Mattrick, President of Interactive Entertainment Business at Microsoft unveils Xbox One on Tuesday, May 21, 2013, in Redmond, Wash. (Photo by Stephen Brashear/Invision for Microsoft/AP Images)

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