PlayStation 4 has sold through 4.2 million units worldwide through December 28, 2013, announced Sony Corporation President and CEO Kazuo Hirai at CES keynote today in Las Vegas.

Sony also announced Gaikai-enabled streaming game service, PlayStation Now (PS Now), which rolls out in US this summer. PS Now streams “popular hits and classic games from the PS3 library’ on PS4 and PS3, followed by PS Vita.

Additionally on most 2014 US models of Sony’s BRAVIA TV lineup, it also allows you to:

• Play video games instantly across multiple devices, similar to the way you might stream TV, movies, and music.
• Stream full games to all of your compatible PlayStation devices including PS4, PS3, and PlayStation Vita as well as non-PlayStation devices, beginning with 2014 BRAVIA TV models and expanding to numerous other Internet-connected devices.
• Always play the most updated version of your game. With games hosted in the cloud, you can take your game with you – just log in with your Sony Entertainment Network account on a compatible device and your games and saved progress will be easily available.

In future, PS Now will expand “beyond PlayStation platforms and Sony devices, allowing you to stream PlayStation games across a broad range of Internet-connected devices,” including tablets and smartphones.

“When it comes to broadband provision, Europe is a considerably more complex region, with a huge number of different providers and varying connection speeds from country to country. In short, we need a little more time to ensure a smooth and successful roll-out,” reads a statement from the firm.

PlayStation Now beta will begin at the end of January in US. The full roll-out is expected in the summer. UK, Europe roll out date & subscription amount is yet to be announced.

Sony’s PS4 leads with 1.2 million units ahead of Microsoft’s Xbox One, with more than 3 million units sold in 13 countries by the end of 2013.

Source: PSBlog.