Today's colossally stupid move by Microsoft: IE 10 turns on Do Not Track by default.http://blogs.technet.com/b/microsoft_on_the_issues/archive/2012/05/31/advancing-consumer-trust-and-privacy-internet-explorer-in-windows-8.aspx
I happen to think DNT is somewhat silly, but if it's going to exist, I'd like it to be meaningful. This removes all chance of that. The advertisers that have so far announced pending support for DNT have generally made that support conditional on DNT representing an explicit user choice -- if it's simply a browser default, many have said they will not honor it (and indeed that is what I'm sure they'll do, as if the ad industry were to actually honor this setting coming from 30% of users, it would gut the entire personalization effort that's been a key industry focus the last few years). In other words, Microsoft have just turned DNT into another P3P -- a worthless and meaningless "standard" that fails to deliver on its intentions.
By contrast, Mozilla, who really want this standard to succeed and have been doing everything in their power to push it, are staying far away from this position.
Microsoft is not so stupid that it would actually do this thinking it was truly advancing the cause of user privacy. I can only imagine that, much like their propositions to default InPrivate browsing/filtering/etc. to "on" in past versions of IE, their position is driven by some kind of belief that they will hurt more heavily-advertising dependent rival companies (take a guess) more than themselves. But even accomplishing that here is now going to depend on convincing the FTC etc. to mandate DNT support even for default-on cases like IE 10.