As Microsoft hasn't really done anything with Media Center since 2008/2009, then it isn't terribly surprising. It is still disappointing, however. As I really do like Media Center.
Personally, I'd prefer if the Xbox One were able to freely view network shared storage. But I doubt that is going to happen. And it likely wouldn't have been able to play MKV's (all my fansubbed animes
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) natively anyway.
I'm going to guess that there is just an increased focus on DNLA. That makes it far more interoperable any consumer electronics DNLA device. So I could see a large focus from them in that area. Possibly more exciting if it can also serve as a DNLA server (no reason why it couldn't with all the resources reserved for the OS).
Regards,
SB