Ethereum Proof of Stake

Einstein: As I understand it, Ethereum plans on at least initially being a hybrid model proof of work and proof of stake. And yet you get to be a hybrid model. It's actually not even as good as that. So the proof of stake will not actually produce any blocks. The idea here is not really that proof of stake adds any security to the system or anything. But if they can reliably produce checkpoints, there's no reason to believe that they wouldn't be able to reliably produce blocks.