Shades of 1984... Except these always-watching, always-listening screens are things you buy voluntarily, and the data is being used commercially. For now.
Is this a different kind of impact than other technology advances have made upon us? I think it's only different in its details, really. As with most other advances, there are benefits and there are drawbacks. Loss of privacy, whether actual or perceived, is definitely a drawback. Convenience and ease of use are definitely benefits - if I can say "Show C-SPAN" rather than picking up the remote, scrolling through the directory to find C-SPAN, and then clicking to show the channel, I'd much prefer the simple voice command.
One thing you can depend on about technology advances: if there's competition, the manufacturers will be falling all over themselves to provide what consumers actually want. If the majority of consumers say they want privacy protection (in particular, if they're willing to pay for that), the manufacturers will be providing it. Unfortunately, it seems that we can also depend on our own government to exploit technology to snoop on us – this I find far more worrisome than the commercial use. Apple's recent cloud encryption decision may point a way for manufacturers to shield their consumers from the possibility of government snooping – and I, for one, would absolutely pay for that!