Microsoft today launched a new thinner, lighter Surface Pro 3 tablet. This 12in Windows tablet offers Core i7 performance in a 9.1mm shell, and you can pre-order it from tomorrow for $799. Here's our Surface Pro 3 launch video and Surface Pro 3 launch blog. See also: Microsoft Surface Pro 3 release date, UK price and specs - thinner, lighter more powerful Windows tablet set to take on MacBook AirNew Surface Pro 3 new features and Surface Pro 3 review.

Microsoft expanded the Surface Pro from a 10in display to a full laptop-sized 12 inches. It has made changes to the Type Cover, too, expandoing the trackpad and allowing you click in place the cover for what Microsoft calls 'lapability'. Rumours of a Surface Pro mini proved to be unfounded.

You can pre-order Surface Pro 3 from tomorrow, May 21, and it will be onsale beginning June 20 in Canada and the United States. By the end of August, Surface Pro 3 and select new accessories will become available for purchase in 26 additional markets, including the UK. We will update this info as it comes in.

Surface Pro 3 launch: as it happened

At a press event in New York, Microsoft today unveiled its anticipated new Surface product: the Surface Pro 3. We brought you the best live coverage on this page, and now you can relive it by clicking the video and blog above.

Microsft Surface Pro 3 and Surface mini launch live

While the Surface Pro 3 and Surface mini were always the two most likely product launches, we had hoped that Microsoft could also announce a Surface maxi, Surface mini Pro or even a SurfaceBook. Microsoft referenced the Surface Pro 3 on its support pages but insisted that it was merely a typo. Turns out it wasn't! See also: Top 8 best Windows 8 tablets: the best Windows 8 tablets you can buy.

We thought that the Surface mini was likely to tip up since Microsoft's invitation for the event said "Join us for a small gathering". We expected that tablet to feature a screen around 7- and 8in so it would be a Windows-powered rival to the iPad mini 2 and Nexus 7. Instead Microsoft has retooled its messaging. The Surface Pro 3 is pitched against the MacBook Air rather than the iPad. Microsoft wants it to be the tablet people use to do work, rather than a consumption device. And it wants people to think of Surface Pro 3 when they are in the market for a laptop.

Microsoft Surface mini launch event invitation

We were expecting a digitizer pen of some sort, and we were right. And we were delighted to see that there is a Core i7 chip in the new Surface Pro, and that the rumoured new versions of the Surface Type Covers with improved touch pads were true.

For us, the Surface maxi always seemed the least likely but a surprise announcement of a more laptop-style Surface sounded plausible - and that is what we got. 'A Surface Pro Book or SurfaceBook would be an Ultrabook version of the tablet which we'd be all for', we said, and the Surface Pro fulfils that brief.

You can get all the latest info on our story: Microsoft Surface Pro 3 release date, UK price and specs - thinner, lighter more powerful Windows tablet set to take on MacBook Air.

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