Very interesting...
About two years ago I went with my Rabbi here to Berkeley and listened to Rabbi Avi Weiss speak. It was shortly after the KSM admissions of guilt which made me very angry... I got upset about something that the Rabbi said and I walked out of his talk... After his talk I approached him and told him my story. He said that I had a right to be upset at the terrorists and I should not forgive them {his speech was about forgiving everyone}.
My Rabbi thinks highly of Avi Weiss... He was called an 'activist' rabbi by my Rabbi. He recently was arrested during a protest of the Iranian dictator speaking at the UN last year. I don't know his feelings toward JTF or Chaim, but I would assume he would stand left of mainstream. I mean that he would support Israel and Aliyah, but would not take the more aggressive stance of JTF which involves relocation, etc...