NYT has a piece on her “temperament”:

…But to detractors, Judge Sotomayor’s sharp-tongued and occasionally combative manner — some lawyers have described her as “difficult” and “nasty” — raises questions about her judicial temperament and willingness to listen. Her demeanor on the bench is an issue that conservatives opposed to her nomination see as a potential vulnerability — and one that Mr. Obama carefully considered before selecting her…. Among the comments from lawyers was that she is a “terror on the bench” who “behaves in an out-of-control manner” and attacks lawyers “for making an argument she doesn’t like.”