Sony is deluding itself if it thinks that they are going to pull off those kinds of numbers. Consumers don't forget too easily what companies do to them. From rootkits and betamax, to ATRAC3? Come on. I'm quite confortable with my DVD library and my DVD player. Not even Sony could stop the production of DVD media, they would be fighting one helluva bad PR campaign against consumers.
What about households who have no interest in the Blu Ray format? It seems that Sony is trying to make the Blu Ray format succeed over DVD by default. In order to ensure that Blu Ray doesn't fail like Betamax did, what better way than to instill fear in consumers. How do you do that? Discontinue the DVD media format, forcing everyone to buy into Blu Ray.
But, there is a problem with that. If you force consumers to buy your product, they won't. Not unless there are huge price drops. Currently, if you shop around, you can purchase a new release DVD movie for anywhere between $13 and $16. Blu Ray movies cost an additional $10. Do the math. If you were a consumer, which would you buy?
To expect Sony to pull off the kind of numbers that they are expecting is going to warrant a miracle of some kind. There aren't many titles available for Blu Ray. TV Shows? They're practically non-existant. Sony risks alienating the studios if they resort to this. And what about those studios who support Blu Ray but who haven't full tilt into the format? Universal, Paramount, Fox, and the rest of the studios are releasing their content on Blu Ray but at nowhere the capacity that Sony wants them to. This is just going to result in even more problems for Sony.
I'm quite happy with my DVD Player and my DVD Library and I don't require anything fancy which would require me to buy a $400 + blu ray player and multitudes of $35 + blu ray disks and a 32" + HD television set.