[DennisP]

> [PoS] enables the rich to seize control of the whole system, and that would enable them to start stealing people's money

This is no more true for PoS than it is for PoW. A 51% miner can't directly steal people's money, because users will reject a chain that does that, even if it's the longest chain. Same goes for a 51% staker. The attacker could double spend in both cases, but with Ethereum the attacker could only do that once, and then would lose all its stake.

And with Ethereum there are no particular "core wallet developer accounts." There's a protocol, an open research community, and a bunch of independent client teams which all have to agree on any changes. Their meetings are public. Ultimately, just as with Bitcoin, it's up to the users whether to run any updates or not.