The requirements for Windows Phone 7 applications to be published in Marketplace have been updated.
You can find the requirements on the AppHub (http://create.msdn.com). Here’s a direct link to the PDF file. The WP7 App Certification Requirements lay out all the policies developers are required to follow in their WP7 apps & games.
You’ll find some new guidance and requirements for media applications. Also maximum size of apps was changed from 400 to 225 MB.
You’ll find a summary at Updated Version of Windows Phone 7 Application Certification Requirements.
Bruce D. Kyle
ISV Architect Evangelist | Microsoft Corporation