water debate heats up

Read the article on the European Space Agency web site about Rosetta's surprising discoveries and how it's cometary water vapour analyses show it to be quite different than Earth's oceans. This seems to be stirring the pot about the origin of water on our planet.

I think I need to read more about this. Can you do an apples-to-apples comparison? Would some variance not occur given time-frames and interactions? That is to say, the water on our planet has been, um, recycled a few times now. It is a vexing question. We're 2/3rds covered with salty water. Where did it all come from?