Wrong, he is still the PM. To pull this off, first they must defeat the government on a confidence motion, then they have to convince the Governor General (who was appointed by the Liberals, and who has ties to Quebec sepratists herself) to hand them power rather than call an election.
Harper has several options. Including pushing off their chance to vote him down for a while, dismissing the GG and putting someone he can trust in there, or can pull the trigger himself and call an election now.
Can Harper just dismiss the GG? That would probably hurt him politically.