I'm not sure it means that he'll be fired. Anthopoulos' contract expires at the end of next season, so it's probably just speculation on the part of these "reporters" that if he doesn't make the playoffs in his final year with the team, his contract won't be renewed. Which, for all intents and purposes, isn't the biggest stretch.
That still doesn't mean it'll happen. The morons at the helm of Toronto sports media have been speculating that AA is on the "hot seat" for three years. They said the Marlins trade was a due or die for him. He's still here.
AA is a professional, and he's already addressed these concerns in an interview a week or two ago, when he said that he's not even thinking about his contract with the team. He said he feels the second you start to look at your own job security is when you start making the wrong kind of decisions for your team. You'd hope every GM feels the same way, but with guys like Moore and Jack-Z out there, we all know that isn't true.