Nuclear first strike?
Fortunately for advertising in general, Mike Zaneis has it wrong. Blocking third-party cookies would be a free gift to the advertising industry, because reducing trackability would raise the average value of online ads.
It's possible for both of these to be true:
This individual ad will have a higher click-through rate if we personalize it to the user.
Online advertising as a whole will be less profitable if we personalize ads to users.
Which makes it an interesting game theory problem. All advertisers would probably do better if nobody used creepy tracking on users, but if some advertisers track users and others don't, the ones who do might be at an advantage. As long as users believe that "online advertisers track and customize" the non-targeters won't get the credibility benefit they deserve.
Firefox fixing the problem at the client software level in a high-profile way is a win. Advertisers who are first to help with making "creepy tracking" harder will be better prepared for the new post-creepy Web.
Let's not get online advertising in general mixed up with specific creepy tracking techniques.