Take a look at this great little document on migrating your web-site to Windows8 Metro style.  The document shows a cool side by side of a web site and what it should look like and how it would work with Windows Metro Style.

Design case study: Website to Metro style app
http://msdn.microsoft.com/en-US/library/windows/apps/hh868264 

Let me know what you think of this document and when you'll be ready to develop your own Metro Style app.

-Scott