Thanks for the infos, these are good news. As I understand, Microsoft wants to support WinRT apps on all devices (PC, Tablet, Phones) which runs the new Windows/Kernel (Win 8 / Win Phone 8 "Apollo"). If this is true, the potential of such HTML5 apps is huge.
Since HTML5-WinRT apps are "real apps", this topic could also correlate with my other thread about SPA.
Keep up the good work.