Microsoft has started to invite the press to the launch of Windows Phone 8. The event will be held in San Francisco on 29 October, and will hopefully reveal the final secrets of the latest mobile OS.

What won't be a secret is the devices that will be on show, as we've already seen hardware from HTC, Nokia and Samsung in recent announcements, although Microsoft has so far prevented us from playing with the software beyond the home screen.

The reason, says Microsoft, is because it hasn't yet announced the full run of features for the next generation of Windows Phone, so hopefully there will be some surprises in store. We're not holding our breath.

What we will be looking out for is which device Steve Ballmer and his Microsoft cohorts choose to demonstrate the new software: HTC told us that the Windows Phone 8X by HTC would be the lead device come launch day.

We already knew that Windows Phone 8 would be landing at the end of October, and HTC has suggested it will be hitting stores with devices a few days later.

READ: Windows Phone 8: The phones to buy

It's set to be a big month for Microsoft, with the launch event for Windows 8 a few days before on 25 October, so you can expect a flurry of Windows excitement to be heading your way.

But will be seeing a device manufactured by Microsoft itself? We don't think so.