Daniel Larimer is a nobody.
He does not know what he is talking about.
Big "conglomerates" doing the bitcoin mining does NOT effect the security of the block chain.
Lets pretend only ONE person in the world is mining bitcoins.
Big deal.
Who cares?
There is nothing that one person can do to hurt bitcoin.
Everyone else using bitcoin has the block chain.
Easily over 1000 people have the block chain downloaded. No I didn't bother to look that up, it is a safe guess.
This one remaining miner cannot change the record, or the records of future transactions.
Perhaps I am missing something, but why does anyone care if everyone STOPS mining bitcoin?
The Bitcoin QT software will still behave as a wallet and peer to peer transaction data will still be shared among everyone elses wallet, correct?
Or are miners acting as a control node, in addition to mining?
No, Bitcoin completely depends on mining to operate. A miner in control could completely destroy Bitcoin if they wanted to. if they had a chain that took more work they could release it any time and wipe out all the transactions and miner rewards during the period they mining in secret.