Does the move to HTML 5 apps render the app "arms race" obsolete?

We've seen Cut the Rope and Grooveshark among others roll out HTML 5 apps. Now we all know Windows Phone faces a pretty large "app deficit" when compared to iOS and Android and Microsoft is working on rectifying that, but does the move to HTML 5 render this argument obsolete? Critics have hammered this app deficit point as almost the singular reason why Windows Phone will fail, but does the future lie in developers coding one HTML 5 app that is platform agnostic (e.g. works on Windows 8, OSX, iOS, Windows Phone, Android, etc).

Does HTML 5 have the potential to replace native apps? Because if it does, I see the App arms race increasingly becoming obsolete as everyone has access to any app via any platform