I think we've got it: Public Figure + Government Contract + Email Comparing a Black Woman to a Chimpanzee = Job Loss + Public Opprobrium.
A few things:
1. I've seen some commenters making assumptions about Baker--whom, incidentally, I've never met--that seem to me far beyond what this email alone would indicate. These are things like (paraphrasing here) "he's a terrible person," "he's a really evil guy" and so forth. Well, I don't think this email necessarily indicates any of those things. Perfectly nice people can have colossal brain farts. Happens all the time. Also, as they say, there really is no accounting for taste.
2. This doesn't mean that the Job Loss + Public Opprobrium is undeserved. You can't be in that particular position and do something like that without having this happen. It was a perfectly and proper outcome given the circumstances. Everyone is prone to brain farts, yes, but everyone is obligated to suppress them when they are acting in positions of responsibility. I'm sure that brain surgeons are prone to brain farts, too. It's part of their job to make sure that they don't happen during surgery.
3. The moral equivalency I'm seeing from some folks--many of whom I very much like--bugs me. Again, the only connection between the George Bush/chimp stuff and the Michelle Obama/chimp stuff is the chimp. It's the (quite obvious) racism that's the difference.
4. Just so we're clear, I'm one of the (apparently few) people who found nothing particularly racially offensive about the Harold Ford/Playboy ad. I thought it was tacky (and, in fact, I believe that this is what really bothered Bob Corker when he criticized it), but not racially offensive. I am also not really prone to finding a racist or racism under every bed. Stuff like this, for instance, strikes me as just plain silly.
5. Another defense I'm seeing is that this email was "political satire." There is no justification to this. The mere inclusion of the wife of the President of the United States does not make it political. In fact, if you really read the email, there's no political statement at all. The message is just this: black woman + chimpanzee = separated at birth.
Which is, of course, the whole point.