Just saw this thread. This is a huge mistake by MS. Hopefully Silicon Dust is able to bring DVR to the Xbox One through their app. I have an HDHomeRun on my network and would love to be able to use it with the Xbox TV support. Until then, I keep my old HTPC running Windows 8.1 w/ Media Center around.
I wish I could say I was surprised by MS's decision, but after the past few years I'm beginning to believe that they have zero clue how to make products that consumers want. Strange decisions like killing OneDrive placeholders, killing Media Center, releasing crap hardware for their otherwise excellent mobile OS, half-finished Windows releases, releasing hardware that won't properly go to sleep, the list goes on and on.