Read original post by Mazhar Mohammed at Windows Phone Blog
Today I want to tell you about two changes we’re making to Marketplace to help pave the way for new store features and new apps in the months ahead.
First, we’re removing the option to shop for Windows Phone apps from the Zune PC software. Second, as part of a larger Marketplace improvement effort, you’ll soon need Windows Phone 7.5 installed on your phone to buy and download new apps, or update existing ones.
As you’ll see in a moment, most of you likely won’t even notice these changes. Let me elaborate.