just because she is trying to reach out to all americans and isn't just preaching to the choir.
If you didn't notice it, she did give a partisan response but didn't use partisan tones to accomplish it. She basically said that the country has moved on to a Democratic Majority and told the president that you can either join us or get left behind.
I think she did a great job.
I think you might have thought so too if she was endorsing Hillary today instead of Barack.