In a move that is sure to brighten the face of every Windows Phone fan, Acer is set to release a very inexpensive handset for the platform later this year, before Christmas, perhaps opening a new avenue for the WP7 line to finally post some worthy sales numbers.

After all, nearly every reviewer finds Windows Phone to be more than palatable, making its history of weak sales all the more disquieting; for how many different smartphone platforms is there space in the market?

The Acer device, dubbed the ‘Allegro’ is set to retail, without a contract, for 299 Euros, meaning that under contract it could cost next to nothing. That would provide Windows Phone with a strong asset, as the platform would thus become known to bargain-conscious shoppers who are not plussed over what platform their phone runs. It could, in other words, bring in the non-techy crowd to Windows Phone.

The handset itself is has 8 gigabytes of memory, a 3.6 inch WVGA screen, and comes in either white or black. In other words, it toes the very minimum of the Microsoft-decided specs for a Windows Phone device. This, friends, is the bottom of the barrel. And you can celebrate it.

Here’s the reason why this matters: Microsoft has managed to very effectively convince developers to build for Windows Phone. It has done a great job lining up partners, and carriers. But when it came time to find buyers, little has, seemingly, changed. This phone in and of itself is a small piece of a larger Holiday sales game that Microsoft is playing, but it could be a cornerstone; a cheap phone all over Europe could bump sales up noticeably. So when the dust settles, this phone could have been a real player.

That or its just a cheap Windows Phone device that might enjoy little distribution and be quickly forgotten. We’ll have to wait and see.