It turns out that it really helps to have a keyboard to make a post. Permit me now, with the aid of my trusty Model M, to unpack what I said above. The posting used the admittedly irritating expedient of using the title as part of the body (again, typing on a touchscreen blows). Therefore, the first sentence should read:
Don't forget the WIn 8 App store, which will be Microsoft's demonstration of how not to lock down a platform.
The point, then, is that "the whole metro apps thing" will be shooting themselves in the foot, going on MS's record in the field of app stores and product support. All you need to do is look at the magnificence of MSN Music, Plays for Sure(sic), Zune Marketplace, XBLA and the Windows Phone App stores. That's the direction the App store is going in. Legacy support is important to Windows, and one of the reasons for its success and differentiation in the marketplace (cf. OSX, aka "Firewire is so 2005!"), and is critical for its enterprise sales. Microsoft's famed legacy support does not extend towards its consumer-oriented stuff. Again, Microsoft Game Zone, Games for Windows, Games for Windows Live, Win XP's killing of non-USB HOTAS setups, Vista's problems playing audio, the list goes on.
So actually, I didn't say anything about Metro the UI (but if your UI sucks, don't expect to get many consumer sales). What I meant was that the Metro App Store, which is Microsoft's attempt to cash in on the iTunes/Google Play "locked down" app store phenomenon — and yes, like Google Play, MS is just trying to give itself a privileged position, a stamp of quality, with, no doubt, some unworkable DRM thrown in —, will be see sluggish sales, developers being exploited, until ultimately it is rebranded, cast off, and finally put out of service with no regard to the developers who tried to use the App store as their sales portal or the users who purchased apps there. You know, like every other time Microsoft has had an online store/DRM-scheme fail.
You know what they say, don't trust the Goog-lighting stranger from Redmond.