Setting aside the conservative "white guys in peril" clown show that's dominating the corporate media right now, she looks to me to be a very moderate, even fairly conservative, choice for the Supreme Court. The official pundits are expressing relief that she's NOT an "activist liberal."
Frankly, I think an "activist liberal" on the Court would be a refreshing change. She/ he would balance out those 4 right wing ideologues on the Bench (who are each far more radical and ideological in their views than any certifiably "liberal" magistrate remaining in the Federal judiciary). It does not look like Sotomayor is that "liberal" Justice from her record. She has a long record of siding with business over labor and consumers in her decisions.
As far as I know, the last economic populist to serve on the Bench was William O'Douglas. Anyone remember him? Yes, that was a long time ago, wasn't it. The Court under Burger, then Rehnquist, and now Roberts, appears to be returning to its historic role of protecting money and property, of favoring the privileged over the exploited. I don't think Sotomayor's appointment will change that long-running reaction against the Warren Court (which has so far lasted a lot longer than the Warren Court did).
The Republicans and their right wing demagogues are covering themselves in something over this nomination, but it isn't glory. Even this lilly white boy finds the spectacle of fat rich old white guys screaming "racist!" at a Latina to be absolutely galling. I predict a relatively smooth confirmation for Judge Sotomayor, with the Republicans further alienating the fastest growing voter bloc in the country.