Microsoft wants to put an arrow through the heart of Android this Valentine’s Day, and it is turning to a Twitter promotion for help.

You can call it tacky or shameless or savvy online marketing, but in order to enter the contest one must follow @Windowsphone and then publicly announce their intentions to dump their Android device in a “Dear Droid breakup letter.” (If you’ve already made the switch to Windows Phone, one must simply declare their love of Windows Phone).

Microsoft’s Michael Stroh offers a few details:

Option 1: If #DroidRage is breaking your heart, tweet a “Dear Droid” breakup letter with the hashtag #DumpingMyDroid.

Option 2: If you already have a Windows Phone (or just want one), tweet why you love it with the hashtag #ILoveWindowsPhone.

Microsoft is fighting an uphill battle against Android and iPhone as it looks to gain share in the smartphone market, an area where it has achieved little success to date. Will the “Dear Droid” promotion do the trick?

Microsoft plans to pick two winners — chosen at random from the Tweets that arrive before Valentine’s Day concludes. Winners will receive a Windows Phones, as well as an annual Zune Pass and Xbox Live Gold Membership.

We’ve been getting a kick out of reading some of the Dear Droid letters, which you can see here. Here’s my favorite:

Dear Droid, it‘s not me, it‘s you. Your battery failures tell me you don‘t want to be with me anyway. # DumpingMyDroid

And here are a few more: