Microsoft will ship Windows 8 for desktop computers and tablets next year and the updated Windows Phone 7 will have 500 new features.

Microsoft CEO Steve Ballmer said Monday: "As we progress through the year, you ought to expect to hear a lot about Windows 8. Windows 8 slates, tablets, PCs, a variety of different form factors."

The Microsoft chief, who was addressing a developers' meet in Tokyo, also said that the upgraded Windows Phone 7 - to be announced Tuesday - will also have 500 new features.

Announcing that the company has sold over 350 million Windows 7 PCs this year, he said: "We have done a lot in Windows 7 to improve customer satisfaction. We have a brand-new user interface. We have added touch and ink and speech. And yet, as we look forward to the next generation of Windows systems, which will come out next year, there is a whole lot more coming."