While this is of course good news, generally, note that three of these countries---China, Malaysia, and Indonesia--have specific restrictions related to material that is considered offensive there. These are people in revealing clothing or in sexually suggestive poses, religious references, alcohol references, sexual or bathroom humor, and simulated or actual gambling, according to Microsoft.
The addition of new market support occurs through Microsoft's App Hub, which the central location for developers to learn about, find tools and resources for, develop for, and submit apps to the software giant's various platforms like Windows (8), Windows Phone, and the Xbox 360. There are also a few other changes coming to App Hub, Microsoft says, all of which are based on feedback: "Minor enhancements and bug fixes, including improvements that will streamline the payout process and enhance reporting to provide data like crash counts and exceptions to assist in improving your apps."
As always, I feel compelled to remind you that Microsoft's developer resources are second to none. And they're getting better all the time. If you haven't done so recently, be sure to check out the App Hub and see what's happening.