The post below this one talks about the sockpuppet problem. I'd like to add a further thought: The people who pay for socks should realize that their efforts can be self-destructive.
I suspect that the Israelis came to understand this fact during the Lebanon invasion. At that time, they instituted a program called Megaphone, in which youngsters (university students, mostly) inundated various blogs (including mine) with pro-Israel propaganda.
Trouble was, the kids were so damned smug, rage-filled and brimming with unearned resentment that they did absolutely nothing to help the Israeli position. In fact, their inarticulate drive-by rants only made things worse: "Something something Balfour Decision! Something something Hitler! So fuck you you anti-Semitic fuck! We have a perfect right to do whatever we want to whomever we want!"
Seriously, that's what they sounded like. When these youngsters invaded the blogs, spat venom and left in a haughty huff, the result was increased sympathy for the Lebanese and the Palestinians.
That's what you get when you hire kids, of course. Older and wiser Israelis probably could have done the job in a much more persuasive fashion. But talent costs money.
Similarly, I think Axelrod (Obama's attack dog) now understands that he took sockpuppetry too far in 2008. He was, to say the least, unsubtle. The "hit 'em with a billion.sledgehammers" approach created an animus against Obama that never really went away. (Of course, it would help if Obama were a better president.)
On the teabagger right -- well, honestly, I'm not sure how much of that commentary is genuine craziness and how much of it is ersatz craziness. A lot of it, I fear, is real.
In the world of commerce, online fakery can transform potential customers into resentful non-customers. Here's a piece in the Guardian
about ways to spot bogus endorsements. Also see here
But let's offer one caveat: A lot of people belong to the "I live to bitch" brigade. If you research nearly any
product, you'll encounter numerous examples of customers caterwauling about tiny flaws. If not for sockpuppets, the reviews on Amazon and Yelp might paint a misleadingly grim picture. Perhaps we need a few "socked" comments, just to offer a little balance. A modest amount of astroturf may be better than no green at all.