Not really, but it makes a good headline. Here's what the Pope said, per Rocco Palma:
Closing out the daylong trek with a Mass – in a rarity for pontifical liturgies, a Sunday vigil – along the shore of the Ionian Sea, the Pope tackled the area's tormented legacy of organized crime, declaring that 'ndrangheta, the locally-based syndicate widely thought to be Italy's most feared Mafia branch, "is this: the adoration of evil and contempt of the common good."
Going further, and lifting his head from his prepared text, Papa Bergoglio said that "those who in their lives have taken this evil road, this road of evil, such as the mafiosi, they are not in communion with God – they are excommunicated!"
As Rocco himself points out, though:
Back to today, while canonists will take pains to emphasize that the "excommunicated" statement is by no means a formal decree with legal effect, in terms of the symbolics and public perception, its potency would be difficult to overestimate.
This is significant and must be emphasized. Not because mafiosi aren't bad people or somehow undeserving of whatever penalty the Church might dole out, but because people are always asking the question of why prelates complicit in the abuse scandal were not excommed. Again, not to say the Pope couldn't/shouldn't do that or make permanent provisions in canon law for doing so. But because he hasn't and people will want to know why.
The fact is that this statement doesn't add up to such a thing for mobsters either and we should remember that.
But hey, while we're excomming the Mafia, how about going after the Lavender Mafia next? They're way worse than the Cosa Nostra folks just by their desecration of their priestly and episcopal office.