I don't know whether Comcast is using IP to deliver their video-on-demand services to your cable box, but let's assume they are. That IP bandwidth is above and beyond whatever you're paying for as a "broadband" connection, but that's just accounting: It's all packets in the end. Is it "neutral" for Comcast to be able to use that bandwidth to provide you with movies and TV while restricting NetFlix to your capped/metered "Internet" bandwidth?

If NN would disallow such restrictions, then Comcast really is a low margin dumb pipe provider. Some people love that idea, but it doesn't encourage any of the existing broadband providers (maybe sans Google) to keep spending tens of billions of dollars to roll out faster and faster networks.

If NN doesn't apply to these services, then of course Comcast will simply package up as much of their IP-based applications and content as possible into proprietary interfaces with your TV and other devices while making the bandwidth available to "open" IP applications commensurately smaller.

If you want to know what the world looks like without network neutrality just go back to the days of Compuserve, Prodigy, Genie, AOL, et al. Dismal does't even begin to describe the situation.