It seems like everyone is just dying to add social features to their online tools these days. One example: Google recent move to expose your "shared" items from Google Reader to your Gmail contacts. Actually, I don't think that this is such a bad idea, but there are other opinions about that.
Scoble thinks that the Reader team should have done a better job of implementing granular privacy controls. Part of me agrees with him, but I wonder, how will we all ever manage fine grained privacy controls on hundreds of sites? You thought having to keep passwords straight for all those sites was tough?
I'm more inclined to wonder who exactly people thought they were "sharing" their news items with and whether they understood the meaning of share. I never had any expectation but that anything I shared would be publicly accessible--not because I looked, but because that's what "share" communicated to me.
The real answer is user-control, but not in the form of fine grained privacy controls, as Robert suggests. Rather, when the data is on a server you control and being shared in ways that you determined, then you get the fine grained privacy control that you want and only have to do it in one place.
If you're using someone else's service, for free, and expecting that you'll get control over everything then you're just not facing the practical reality of the situation.