As for the 'not a sure thing', who do think will put $10 billion into an alterative at this point? Only Microsoft has that kind of money and they a betting on an on line approach.You're assuming somebody will put $10B into it and I'm saying they won't. Sony is playing with themselves again and the buying public's mind is wandering.
There was never a burning interest (except with us cinephiles) for a really high-rez video disc format. Much of the buying public thinks DVD *is* HD, and a lot of the so-called HD programming on cable is really upconverted 480p.
1080p Blu-ray fed into a 1080p display IS stunning, and noticeably better than typical resolution in a movie theater, let alone standard def DVD, upconverted or not. The public needs to be shown that there's a difference and that the difference matters. That window of opportunity is disappearing fast, and people will settle for cable HD and upconverted std-def DVDs.