What are your thoughts on the �Jesus Myth� hypothesis?

Is it pretty convincing the fact that nothing in Christianity is original but just borrowed from ancient pagan and mystery cults? Everything: Jesus's cirstances of birth, born from a god and a human woman --Horus, Dionysus--, His life based on other historical and mythical characters: --Buddha, Moses, Dionysus, Horus, Mythras, Jehoshua Ben-Pandira--, the miracles, the rituals taken from Judaism, the Holy Water taken from the Egyptian traditions, the Eucharist taken from Mythraism, the crucifixion, --Mithra, Horus, Krishna-- and the resurrection on the 3rd day, and the becoming the Judge of Sinners --Osiris--.