Well, if I may explain my personal opinion on the matter, it has to do with differences in the level of complexity.
Judaism: Belief in one supreme God who occasionally interacts with mankind, and communicates via prophets.
Islam: Belief in one supreme God who occasionally interacts with mankind, and communicates via prophets, esp. via his prophet Muhammad.
Christianity: Belief in one supreme God who very often interacts with mankind and who in the past decided to taint all of humankind with the Original Sin over- of all things- a fruit, and who decided to impregnate a virgin so that he could put his soul inside her womb and be born as a man so that he could live as a human being for thirty years, turning water into wine, healing the sick, healing the blind, walking on water, raising the dead, be arrested, tortured, brutally executed, and then resurrected so that whoever believes in him is no longer tainted with the curse of Original Sin that HE himself put on mankind in the first place, and that every Sunday he must be honored by eating his flesh and drinking his blood, by fear of burning in the flames of Hell for eternity.
Correct me if I've gotten anything wrong.
So if you are a Christian, please put yourself in the shoes of a non-Christian (hmm what do you call us again, heathens?) and try to imagine how it all sounds to us...
The simple fact that Christianity is based on central themes of such convoluted unsubstantiated complexity, is the reason why it attracts the rants of atheists so much more than Judaism or Islam. Imagine a big, flashy, Las-Vegas-style neon sign that says "Look at me! Look at what I believe in! Come on join the club or your immortal soul will BURN IN HELL!"
That, in a nutshell, is the reason why.
Peace be with you.