如何在Windows 8 Metro App中处理HTML内容

I'm designing a Windows 8 Reader App, and I have to use a control to show the HTML content, which is fetched from some website feeds. Cause those HTML content may contains images or some other formatted text, now I'm using a richtextblock to show the HTML content, but it costs a lot of time to parse the HTML content.I'm designing a Windows 8 Reader App, and I hav