I really think it's just that Metro/WinRT is the new thing, they're always going to be trumpeting the new features of the new release as if they're the only thing anyone should care about, that's unfortunately a Microsoft habit. The desktop will quietly continue to persist and evolve.

I don't expect much success with Windows 8, due to a combination of there being a lot of genuine rough edges and gaps in the new environment and in how it relates to the desktop, most people not really feeling a need for a new version of Windows right now anyway, and people's normal resistance to change. However, they'll probably continue to improve the Metro stuff in future Windows versions, and eventually it will just become another boring established part of Windows that everyone takes for granted. At which point it won't be the new shiny anymore and balance will be restored.