The Buddha didn't say he was coming back. The Buddha said that there would be a future Buddha at some point: Maitreya. That could be many thousands of years away.
In Buddhism we forsake God, we explicitly reject Him. We reject all creation, and embrace only the dark: emptiness, in which all things are fundamentally non-distinct.
"Eat, drink, and be merry, for tomorrow we die"? I might not live for thousands of years, but would like to make the world a little better during this time here.
Please let's not derail this conversation into religious debate here. I love talking about philosophy, and if you'd like to talk more about absolute/relative morality, I am currently online for a video/audio/text chat on the BeWelcome chatroom.
