I submit many points at this juncture:
- The god of the Jews and Christians does have a name. It's "Yahweh." The four-letter spelling of that name in Hebrew is referred to as the Tetragrammaton.
- One of the world's largest and most dogmatic religions, Islam, has been growing rapidly for decades. Admittedly, this is largely the result of population growth in Muslim countries, but there have also been "fundamentalist" movements in many Islamic countries over the past few decades.
- There are still one billion Catholics and a billion Muslims in the world. Given that these two religions have been around for about two thousand and fourteen hundred years (respectively), I don't think they will disappear in the short span you mention. Perhaps that's just my opinion. Judaism (though not in its modern form) has been with us for more than five thousand years. It's proven to be one of the most robust religions around.
- I submit that the ideas of the ancient Greeks and Romans continue to permeate the Christian experience. Technically, as pontifex maximus, the Pope is still the chief priest of the Roman Empire. I will get into the contributions of the Neoplatonist school elsewhere.
- It's dangerous to equate the decline in American church attendance/belief with broader trends worldwide. Darn it, those barbarians just aren't as sophisticated as we are (sarcasm, BTW!).
- I'm not qualified to get into a discussion of Buddhism, save to say that it's been with us longer than Christianity and has shown surprising traction in the West. Then there's the question of where spirituality ends and faith in a religion begins...do you submit that we are becoming an aspiritual world?
Sorry if this sounds like a flame...not my intent!