EDIT: Such a power can come only from a big organization or a state. If the same attack our RSA keys, they will broke them in few days!
No^^ they won't just break the keys with this. 150 GHs is not that much
Anyway, if you read about these kind of things (its still possible that there is no attack at all) an "attacker" can't do much to the network, or to the coins that already have been transferred.