If the quality of the streamed content were any good, I'd be a lot more vocal advocate for its wider use, but...
And when I'm talking about quality of the streamed content, I'm not talking the relative artistic merits of watching American Idol streamed, I'm talking about things that can be assessed objectively like audio and video bandwidth, the amount of pixellation, etc...
I spent a lot of money on my television and AVR and speakers. But when you watch streamed content over your cable hook-up, you're not even close to being in the same league as DVD, let alone Blu Ray.
Most evenings, I can usually connect to the internet at around 21 or 22 Mbps (as measured by
www.speakeasy.net/speedtest ), and when I stream NetFlix, it's just not what I signed up for when I opted to buy a 50-inch plasma display with amazing black levels and an incredible picture. Heck, if you're gonna watch streamed content, you might as well bring back your old 480i tube TV. And let's not even get started on things like stereo only or dropped frames.
I suppose crap like streamed content is useful if all you're watching it on is your smart phone, but for high-quality A/V experience, it's lame.