The Senate Judiciary Committed confirmation hearings on the nomination of Sonia Sotomayor to be an Associate Justice of the Supreme Court began today. In spite of the strong opposition of some of the Republican members of the committee, it's all but certain that Sotomayor will be confirmed. Although at times she has made statements that were ill-considered, such as her statement about "wise Latina" judges making better decisions then white men, Sotomayor's record is solidly in the judicial mainstream . Overall her reocrd is slightly more liberal then the average judge nominated by a Democrat, but there's nothing at all indicating she's an extremist.
Here's a good article that discusses just how much in the mainstream Sotomayor is.
An article on how moderate her record in criminal law is
She has been endorsed by over 1000 law school professors.
Sotomayor's rise from a poor childhood in the South Bronx to a likely Supreme Court Justice has frequently been discussed, This article provides a brief biography.