From Colby Cosh, the hirsute one himself:
Early commentary on Burke’s lawsuit over claims he had an affair with a broadcaster was focused on the difficulty of tracking down internet anonymice and serving them with the right papers. The established pathway is to go through internet service providers to get them to disclose the identities behind IP addresses—but privacy-conscious tech firms don’t like to give up that info without a court order, and if Johnny Flapgums did not happen to post from home or work, a plaintiff is more or less out of luck anyway. In an unforeseen development, Burke is now asking the court to let him sue internet usernames as usernames, notifying the users of the action through the personal-messaging apparatus of the sites on which they posted their allegedly scurrilous comments.
If Burke succeeds with today’s motion, defendants such as “CamBarkerFan” and “Slobberface” will be forced into a tricky choice between fighting the lawsuit, and thus exposing themselves to a verdict, or laying low and allowing a default judgment to be entered against them, thus exposing themselves to the risk of being identified and penalized later without any chance of a defence.
If this kind of thing had been allowed a few years back, the whole slow process of serving anonymous posters involved in theFreeD vs. Richard Warman case would have been made alot easier. To quote myself, tracking them over the Net at the time involved:
...going from blogs to the comments section of online newspapers to flickr and elsewhere.
Essentially, you are hoping that the defamer behind the pseud got lazy and at some point wrote something that connected the handle they used to produce the defamation with a separate profile employing their real name. Then you pore over their on-line traces looking for that link. So, for example, Droid1963 wrote a blog under his real name, and linked to a photo-bucket album. He was eventually forced to settle.