We’ve known for a little while that Microsoft was working on its own application store for Windows Mobile-powered devices. However, details surrounding the store have been pretty vague until now. Thanks to some new information from Microsoft, we now know more about its application store, which will be called the Windows Marketplace. For starters, the company plans to charge developers an annual fee of $99 to become part of the Windows Marketplace ecosystem. There will be an additional $99 fee for every application