Georgec: I think you're missing my point. I don't deny that Islam claims to be the continuation (actually, the "abrogation") of Christianity, nor that Christianity claims to be the continuation (actually, the "fulfillment") of Judaism. My point is simply that from the perspective of a study of comparative religions, each of the three communities of faith ascribe to God characteristics that are mutually exclusive of the other two ascriptions. Therefore, to claim that the Muslim's God and the Christian's God are the same, is really unacceptable to both faiths--assuming we allow each faith community to set its own terms. So if the Christian God is described as Father, Son, and Holy Spirit, equal in essence yet distinct in person, that definition will fall short of a Muslim's definition of God. And conversely, if the Islamic God is defined as a singular essence and a singular person, and nuanced in such a way as to explicitly deny divine status to Jesus, then that definition will fall far short of a Christian's definition of God.

The differences are therefore irreconcilable, and my comment about arrogance and fallaciousness was directed against those who would claim that they (the differences) are not.