Poor Nokia. Things looked promising when the Finnish company first inked its deal with Microsoft to only release Windows Phone handsets. But now, that partnership is holding it back, as the N900 illustrates.

Let’s just get this right out of the way: The Lumia 800 is a gorgeous phone. The Lumia 900 is essentially the exact same phone, but bigger. The camera works well, the buttons are well placed and the build quality is superb. It has the same processor, the same RAM, the same storage… Even the same screen resolution, despite the extra real estate.

And therein lies the problem. The N900 is a well built smartphone. It’s nice to look at, relatively comfortable to hold (if a little bit chunky) and performs reasonably well, thanks to Windows Phone 7’s operating system.

But when you compare it to the likes of the HTC One X, One XL or Samsung Galaxy S III, the phone feels primitive. The 800 x 480 screen, for example, is underwhelming at 4.3 inches. While the Live Tiles look fine, trying to read text through Internet Explorer pales in comparison to the high resolution screens Android and iOS are releasing.

The single core 1.4 GHz processor is another conundrum. The Lumia doesn’t necessarily lag, but it does falter with some apps (playing Civilization, for example). In a world where quad-core processors are becoming the norm, having such a low powered processor may help battery life, but it doesn’t help performance.

And the reason these drawbacks are part of the Lumia 900? Microsoft. The Windows Phone specification is very precise, only supporting phones with single core processors and screen resolutions of up to 480 x 800.

Given that the Windows Phone 7 specification is a few years old, this is really disappointing, especially for Nokia fans hoping to experience an exciting new age of dominance.

The good news is that Microsoft has announced its upgrade to the platforms minimum specs when it releases Windows Phone 8 later this year, and it accounts for these shortcomings. But before you rush out and buy the Lumia 900 in the hopes of getting Windows Phone 8, we should point out that Microsoft has stated that no current Wondows Phone will support the new platform.

In other words, the Lumia 900, which came out just months ago, will be obsolete in a few months. And even though it’s an enjoyable handset to use, it’s hard to recommend something when it’s already been left behind.