Nokia's Lumia 900 on AT&T has been delayed to April, but the release date is still not known. We know it will be $100 on contract, but when Windows 8 rolls out at the end of the year, how much of it will be included on Lumia phones?

Microsoft is redesigning its desktop operating system to look more like the Windows Phone system for mobile devices. But we don't know how much of the new system will actually make it to the mobile phones. The Metro style interface will be there, but the level of integration between the two systems is what we're thinking about. Specifically, if Microsoft changes the hardware requirements on mobile devices running the system, how many Windows Phone 7.5 devices will be able to run Windows Phone 8?

If Microsoft wants to get serious about contending with Apple on phones and tablets, they need to get this one right. Some developers are already using Windows Phone apps on the Windows 8 Consumer Preview edition, tech blog The Verge reported, so that bodes well. If Microsoft can manage to build an operating system that looks and feels very similar on phones, tablets and PCs, it will have created a very powerful ecosystem indeed. We just wonder how well it will work on current Windows Phone devices because of the new hardware requirements rumored to be included in the next system update.

For example, there aren't any dual-core processors on Windows Phone devices, and the native resolution on those phones is only 800x480p. The next generation of Windows Phone devices will have better resolution and more powerful processors, naturally. We just wonder how many of the first Windows Phone devices will get left behind when the new system debuts. Lumia 900, being the flagship, may not be affected, but the HTC Titans and Samsung Focus Ss of the world could miss out.

As for the Lumia 900 release date, the two dates we're seeing are both from anonymous sources. We've heard an April 22 date from tech blog BGR. However, we've also seen an April 8 release date from a forum post on The Verge. The poster says he works at an AT&T store.

Start the slideshow to learn more about the Lumia 900 and let us know in the comments if you think it's worth the $100 price tag.

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