Sending Clinton to Israel is an excellent move by the Obama administration. She's higher ranking than Mitchell and she carries credibility and pro-Israel presumption. She also signals that the settlement freeze is a priority for the Obama administration. Clinton is now getting grief from the Arab states for supporting what they feel are inconsistent concessions, but this is pretty clearly for political purposes rather then out of a genuine feeling that the U.S. is selling out the Arab world. At this point it's unrealistic to think there will be a total settlement freeze, at least without any Palestinian concession, but to the extent that progress is possible, Clinton is doing a pretty good job.