There's an argument for removing the ability to be anonymous, but I think it's pretty much superior to allow people to hide their identity, but take their statements with all of the doubt that you would an anonymous, gossipy rumor. Trolls will be trolls, and the best thing to do is ignore them, not try to out them and ruin their professional lives.
On the other hand, posters like Pauliewalnuts, lonelyvirgin, and :D bordered on being sociopathic and I feel like those guys are getting what was coming to them. I also think there's an enormous difference between, for example, expressing desire to have sex with someone (locker-room banter) and making jokes about becoming forceful with that person, which most women would take as a threat.
No. Not a right, especially when performing constitutionally-protected actions. I don't believe people should be required to identify themselves online, but I do believe that people who post anonymously should expect to be exposed eventually.
A better question would be whether legal channels should be used in the exposure of an anonymous person.
I believe so only if all other option are exhausted.
"Do the pros outweigh the cons?"
Yes, but only in place where free speech is not protected by the state.
However, I'm very happy that those individuals who were identified have faced social repercussions for their behavior. I would not want anything to do with any of those posters. If I were hiring, I wouldn't hire any of them. I would probably boycott any businesses that work with them. If they're free to be jerks, I'm free take my business elsewhere.
Therein lies the more interesting issue. Anonymity. It's hard to exert social pressure on bad behavior if you can't identify the people involved. Do we have a right to be anonymous online? Do the pros outweigh the cons?
I really don't know...