I'd have to agree, though, that the default of following everyone that you e-mail is a bit extreme, especially if everyone else can see it, too. Probably better to at least offer people a choice, either follow all, follow none, or manually select.
As far as privacy violations go, though, I don't see this one as very major. I'd expect that with all the complaining going on, this behavior will be changed very soon.
It was available for mobile users immediately, but it also didn't seem to be integrated into mobile GMail when I first looked at it.
So, Buzz would be fine if it just left everything alone, but I would be pissed if I actually used Picasa or Reader and my activity got published without my explicit approval.
I also want to control who can follow me -- if that option exists right now, I haven't found it. I don't want casual acquaintances or workmates to see things I post, even if they've subscribed to me.
Besides the point though. They opt you into a service you didn't sign up for, and require you to take measured steps to preserve your privacy.
It's good for Google, whether its a good default or not is debatable.