*Ahem* well,
There is a differance between Anonymous and the sites they frequent, and chances are if Anonymous had actually been ticked off they would have done something rather than just made some ongoing comments. It's not like anyone ordered a ton of unpaid for "gut buster" pizzas and had them sent to your friend's address, got his internet locked out, spammed him with black faxes, started publishing dox all over the place, registered him on offensive porn sites, and similar things... which are among the forms of actual harassment Anonymous, and hackers in general, tend to use. Take a look at some of the acts recorded on sites like Encyclopedia Dramatica where Anonymous *DID* single people out, and then look at your friend. From what your describing there doesn't seem to be much similarity from where I'm sitting.
My immediate guess is that your friend has simply made himself a Lolcow by acting nervous when someone said something. Thus by sending a stereotypical message here and there they pretty much ratchet up the nervousness for lulz.... since it inspires messages like this
one. Basically I think it's people claiming to be Anonymous, rather than Anonymous itself.
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As far as Anonymous goes for real though, I can understand the concern since I wouldn't want to cross them. Irregardless of what people might theorize the members are like, the damage/harassment they can do is real, and there is very little that any individual can do, which is part of the point.
See, the point is that there are tons of members (we won't get into theories about how it all works). Even if you had the abillity to single out and find one of these guys, grabbed a greyhound to his area of residence, bought a sledgehammer from a local store, busted into his house, and worked him over, you would accomplish absolutly nothing against Anonymous as a whole. That's one guy, and nobody could get them all. That's why being an "internet tough guy" is irrelevent in that case because even if your serious and do have the abillity to do something, your simply that badly outnumbered. Even if your "good at the internet" you can't out hack them all, even if you have training, and investigation / violence-oriented skills IRL you can't find and deal with them all, heck even if you somehow did find them, you'd have to be rich to track them all down, and chances are if you had those kinds of resources you wouldn't have been doing whatever it was that got Anonymous' attention to begin with... and truthfully if big groups like say Scientologists and The Australian Goverment can't engage in any kind of meaningful retaliation, one dude isn't going to be able to, even if he's James Bond.
I'm no expert but that's how I understand things, and what I've seen. Tell your friend not to worry in this case, because really, I think he'd have seen a bit more if this group was actually actively persecuting him. I also think it takes a bit more than some comments on Youtube to capture their interest/imagination. Most of the victims I've seen record of had more behind them than simple comments on youtube, though that might have been part of it.
