The Ethics of ‘Outing’ an Anonymous Commenter

There is a battle raging on one of my favorite blogs, PSFK, about a new campaign for Levi's from Wieden + Kennedy [that's an advertising agency for those of you who don't live in the echo chamber].  If you're interested, check out the post and comments here.

But this post isn't about the campaign, but rather something I noticed in the comment thread.  Someone, identifying herself only as "megan," left an anonymous comment for Piers Fawkes [who wrote the post] saying "your negative rants on wk are getting boring."

I happen to believe that anonymous commenting is pretty cowardly.  But I'm neither naive nor dogmatic about it - I realize that for a variety of reasons people sometimes feel they need to hide their identity, or just aren't comfortable identifying themselves.  But still, I'm not a big fan.  Apparently Piers has a zero tolerance policy, judging by his 'outing' of Megan as a W+K employee

FireShot capture #135 - 'Levi’s Does An Abercrombie & Fitch - PSFK_com' - www_psfk_com_2009_07_levis-does-an-abercrombie-fitch_html

So the question I pose [and I invite Piers to respond, and I hope he appreciates the spirit in which this post is drafted] is, what are the ethical standards for a blogger 'outing' an anonymous commenter? 

Do we owe our readers a disclaimer that their identity may be revealed, despite their desire for anonymity?

As masters of our own domain (pun intended) do we have a right to do anything we want with the back-end analytics at our fingertips?

What's the upside of 'outing' commenters?  Does it level the playing field?  Force people to own up to their words?

Please leave your comments - I hope the subject-matter here compels you to leave your name.