I've been learning to the cynical and evil explanation, but a comment by Google's CEO, Eric Schmidt, has changed my mind ...
This is an outrageous statement. Schmidt cannot know that nobody was harmed, either directly through the bonding of Buzz streams to public profiles or indirectly through inevitable misunderstanding. Even if he were omniscient, since many people have felt harm, it's a stupid thing for a CEO to say.
So why does this make me feel that Google is more incompetent than evil?
Because in my experience someone who says something that's obviously wrong most often believes what they are saying.
Which brings me to my corporate diagnosis. We can do that now that our courts have decided that corporations are people. I am a physician after all.
Google has Asperger(s) syndrome. For Google, people are an slippery and elusive concept. It explains a lot.
PS. I don't care what the DSM V says about Aspergers, it's a useful concept.
Update 2/22/2010: I think the person responsible for Buzz is also responsible for the obstinate Gmail message thread-by-subject-line model. Same sort of stubborn certainty.