I don't really disagree with you as much as you might imagine; I wouldn't buy an SD camera right now either. However, what's good for the goose is not always what's good for the gander, and no sweeping generalization is going to apply in all cases.
Likewise, it may not be about DVD's to you, but someone else might be planning entirely on self-distribution and not at all worried about the needs or requirements of theatrical distributors, broadcasters, etc. And my point with the BD thing was simply meant to illustrate that HD is not exactly being adopted as widely as we might like to believe. And bear in mind that when U.S. broadcasters make the switch to digital broadcasts in 2009, it doesn't necessarily mean that all television will suddenly be in HD--it just means that analog receivers will no longer work. Who knows what the cable channels will be doing?
Again, your situation doesn't apply across the board, and yet it kind of sounds like you're suggesting that it does.
"I would not buy an SD camera right now" is not the same as "YOU should not buy an SD camera right now." That's all I'm saying.