Up until now, Microsoft has taken a rather laissez faire attitude toward application development -- anyone with a copy of Visual Studio and half an ounce of coding know-how could whip up and share whatever little programs they want. That won't be the case inside Windows Marketplace for Mobile, Microsoft's answer to the App Store, and the company is now listing a number of guidelines that devs must follow for the fruits of their labor to be included. Top on the prohibited list? Apps that themselves sell other apps. Second rule of the Marketplace? No apps that link to apps that sell other
