In 2005, Geoge W. Bush stated that it is "unrealistic to expect that the outcome of final status negotiations will be a full and complete return to the armistice lines of 1949" (the 1967 boundaries of Israel, in other words). Today, Barack Obama said that he believes "the borders of Israel and Palestine should be based on the 1967 lines with mutually agreed swaps, so that secure and recognized borders are established for both states." I take this to mean that Israel would retain its major settlement blocs; that it would retain the Jewish neighborhoods of East Jerusalem, and that it would take West Bank land needed to thicken it at its most narrow point, in exchange for land adjacent to the Gaza Strip and the southern West Bank. I also interpret the saying "mutually agreed upon" to mean, well, "mutually agreed upon." In other words, these boundaries would not be set without Israel's approval.
I understand that Prime Minister Netanyahu is interpreting this as a major policy shift, and I understand that much of the media is going along with this interpretation. For what it's worth, I don't see a huge gap in the way these two Presidents framed the core issue.