[0] Mobile "broadband" doesn't count. In most places, it is entirely unsuitable for streaming high-def video and will be for several years.
My TV provider offers films on demand at £2-4 per viewing. The convenience of being able to watch immediately, and cheaply outweighs the choice of buying the DVD/BR and being able to watch multiple times.
Quick cost comparison:
1) Stream it for £4. Film was rubbish. Total cost = £4.
2) Stream it for £4. Film was great. Wait a few months until price falls. Purchase DVD at discount for £5-£10. Total cost = £9-£14
3) After release purchase for £15. Total cost = £15.
Of course this depends on the economics of your specific location and the cost differences, but personally I think I spend less in total on films because I very rarely buy physical media until the prices fall.
Streaming to a PC fits a very similar market profile, the only difference being it caters to those who build their entertainment system around a PC rather than a regular TV, and I think the lines between those as two separate systems are going to increasing blur in the coming years.
Right, that's why Netflix Instant is such a failure.
This is night and day different from what Hollywood wants to do, and what Intel is trying to enable them to do: force consumers to buy physical discs, or force consumers to rent from a hardware-enforced DRM'd digital kiosk.