Camel / nose / tent.
The 1st couple of releases will allow for older interfaces. But as time goes on they do NOT want to support multiple pathways and front ends to the same apps, especially when they are betting a huge chunk of cash (and what they think is the future of the company). But they won't simply turn it off. They'll introduce a series of API shims to allow a single core interface library to control it all. But then the shims CANNOT execute the same way, there will be incompatibilities. Since their programming guidelines will always push people to use the new stuff, in such a way it can't be using the old paths it will lock them in. And then they will turn off / break various interfaces to push the programmers along to their preferred direction.
And hope the clueless make enough noise to support them.
To paraphrase someone I occasionally respect, but rarely in programming conversations since he really is clueless and has stated many times in the past he doesn't give a shit about these things or the level of effort the coders have to deal with:
"Non programmers" should shut the fuck up about Windows 8 (which "they" can't control) and get on with "fucking around with their toys that they don't want to understand" ("even when they" can). "They" should definitely shut the fuck up about user interfaces.
teehee