I suspect that it's because they are wanting to implement a server, client type of thing. In the future we may see that the DVR part like the HR54 become server only and put into a media closet or cable closet, and all TV locations have a thin client. It's easier this way and does not require DVR's to be placed all over the house. It would not surprise me to see the video outputs drop off and setup is completed through a web gui.
Basically you have one giant server storing and getting video from every source to man, (Satellite, Internet, ect.) and all of your clients get your video from it to include your smartphone as a client that can access your video outside of the home. The server you wont be charged for but the clients you will.
this would be fine, if it has more than 5 tuners
and there was no fee for the server