Just a matter of days before an expected official launch at the Nokia World event, some of the wind has been taken out of both Nokia and Microsoft's sails with the leak of official press shots of the Nokia 800.As you might already know, this is the flagship Nokia Windows Phone and (Nokia hopes), the start of the company's fightback with an all-new OS on-board. New to Nokia anyway, as Windows Phone 7.5 Mango is already making inroads into older Windows phones.These fresh images, presumably ready to hit press inboxes on the morning of the 26 October (the start of Nokia World), come to us via Pocket Now. They show a phone in three colours (black, as well as the blue and pink pictured), not a million miles from the N9, which never quite made it to market. It's a slim design with a minimalist look, some controls for power, volume and possibly camera on the side, with a speaker at the lower end of the phone. After that, it's all about that 3.7-inch touch-screen.Other details are still to be confirmed, but with just days before the official unveil, you'll know soon enough. Nokia does have a bit of a track record of delays between unveils and shelf dates for its flagship phones, but the Nokia 800 could be different. Pocket Now is also reporting a 15 November date for sales of the Mango phone, just three weeks after the launch.After that, the hard work begins for both Nokia and Microsoft – convincing us that the Nokia 800 is a better bet than than Samsung Galaxy Nexus or the iPhone 4S.