Microsoft has confirmed the hardware partners that will be launching Windows Phone 7 handsets, at a one-to-one briefing with Pocket-lint.

Although the company still wouldn't be drawn on any specific dates for the launch of the new mobile phone operating system, beyond some time in the "Holidays", it was happy to tell us who was making the devices for day one sales.

Greg Sullivan, senior product manager for Microsoft, told Pocket-lint that we could expect handsets from Dell, Asus, LG, HTC, and Samsung at the launch later this year.

It confirms certain former rumours.

We always thought Dell would be launching a Windows Phone 7 device, the Dell Lightning. And HTC exclusively confirmed to us that it was also launching a Windows Phone 7-powered handset too.

In our meeting, Sullivan referenced an LG Pacific, possibly a renaming of the LG Panther doing the rounds, but refused to be drawn further. 

Microsoft is using a Samsung device for developers to preview and work with the new OS, but has categorically stated that Samsung isn't releasing the handset (pictured) in that form. 

That's five launch handsets, some of which, Microsoft has already confirmed, will include a QWERTY keyboard, as well as a full touch screen experience.

Sullivan also confirmed to Pocket-lint that the operating system would not be exclusive to any one operator in the UK or the US.

"We want as many people as possible to be able to get it", Sullivan told Pocket-lint.

It's a strategy that Microsoft believes will bring it success. Sullivan told us that Microsoft believes it can quickly leapfrog operating systems like Palm's webOS, Nokia's MeeGo and Symbian platforms, Qualcomm's Brew MP, and Samsung's Bada, to become one of the top four operating systems on the market. It hopes to be pitched in with Google (Android), Apple (iPhone), and RIM (BlackBerry).

"We will offer the best aspects of Android and the best of the iPhone, giving users the flexibility of different form factors, but with the rigidity of apps that are guaranteed to work on every device that is out there", Sullivan told us.

However, when we asked whether or not he was hoping to steal users away from Apple's iPhone, or HTC's Android offering, we got a very different answer:

"By the time we will launch, we won't have to worry about stealing customers from other operating systems, there will a new wave of smartphone users to embrace for us to still be successful".

Brave words indeed.