Jeff Soyer writes:

Let’s see, Obama’s kids are “off limits.” Sarah Palin’s aren’t.

It’s a great point. Obama and his supporters have gone so far as to say that comments that Michelle Obama has maid while campaigning for her husband are off limits, but they can say that Sarah’s daughter MUST be the mother of their youngest son, on the strength of Mrs. Palin not showing as much as they think she should.