New Testament scholar Daniel Wallace provides a brief note on the possibility of the number of the beast being 616, not 666, here.
Wallace also refutes Walid Shoebat’s sensational and fallacious claim about a New Testament manuscript and a supposed Arabic insertion, here.
Also, James White one of today’s most effective Christian apologists on Islam debunks Shoebat’s claim, here.
I am concerned about this “feed the eschatology crazed evangelicals with wacky connections to Islam” movement. For those of us attempting to provide solid, sound, consistent answers to Muslims, this kind of presentation is significantly less than helpful.