Sotomayor's trail of opinions paints a picture of a fair-minded, incisive legal scholar who is unafraid to stake out unpopular but legally meritorious positions. Right-wingers are going to oppose her nomination with full force - we would be foolish to do it for them.
I quite agree with that last bit. With regard to her history, I still don't know a lot, but the NYT article has a lot of links, here's a bit on the empathy thing, and here's Obama's own video about it.
ETA: comments lead me to read this Salon.com discussion by Greenwald, which is also good and contains links to more material relevant to the topic.