Nokia's most important phone of the year, announced at an event in New York City this week, is due to reach store shelves in November, according to Reuters. Citing wireless network operator sources, Reuters said the Lumia 920 is planned for a pre-holiday release. Nokia has only said the device will become available during the fourth quarter.

The Verge, citing its own sources from Microsoft and AT&T, says November 2 is the earliest the Lumia 920 will reach the U.S.

Microsoft is still in the process of finalizing the Windows Phone 8 platform. It is prepared to offer the Release to Manufacturing (RTM) version in the next week or so. The RTM is what hardware manufacturers, including Nokia, need to finalize their smartphone designs. Hardware makers have been using pre-release WP8 builds in their device designs, and will need another six to eight weeks to incorporate the RTM and lock everything down.

Microsoft has not yet fully revealed all the details of Windows Phone 8, and is probably controlling the launch timing for its next-gen smartphone platform. Microsoft did this with Windows Phone 7.5, Windows Phone 7, and even Windows Mobile 6.5. Microsoft is prepared to launch Windows 8 (for laptops, desktops, and other devices) in late October. It would not be a stretch to assume that Microsoft will kick off sales of both new platforms--mobile and desktop--at the same time.

[ Will Nokia's phones get a warm reception in the marketplace when they do arrive? Read Nokia Windows Phone 8 Devices Arrive With Thud. ]

That means Nokia and other hardware makers are unable to offer their new hardware, such as the Lumia 920 and 820, to consumers until Microsoft says so.

Is that a big deal? For Nokia, it might be. As they say, it is all in the timing.

Apple is widely expected to debut the iPhone 5 at an event in San Francisco on September 12. The device may reach stores as early as September 21. Demand for the iPhone 4S has slowed ahead of the iPhone 5's launch, which has garnered a lot of interest from consumers. The iPhone 5 should offer a larger display, faster processor, and LTE 4G for the first time. Together, these new features and capabilities could make it a strong seller going into the holiday quarter. If the iPhone 5 does go on sale by the end of September, it could sap the potential market for the Lumia 920.

But Nokia has more than just Apple to worry about. Samsung has already taken the worldwide smartphone lead and is going into the holiday quarter with guns blazing. It recently announced the Galaxy Note 2, which is expected to hit U.S. and world carriers by the end of the year. The Note 2, which features a 5.5-inch display, LTE, and the latest version of Android, could be a surprise hit with American consumers.

Add to these competing Windows Phone 8 products from Samsung, HTC, and others, and Nokia has plenty to worry about. With sales of its existing Lumia devices slumping ahead of the Windows Phone 8 debut, November can't come quickly enough for Nokia.

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