Blizzard warned us it was going to happen. The executioner's axe has fallen and Battle.net is dead. The name, that is, but not the service.
The company quietly swapped out the Battle.net logo on its game launcher so that now it says Blizzard where the old Battle.net logo used to be in the top left corner. The move is the fulfilling of a promise that Blizzard made back in September to phase out use of the term. This was apparently the last step in nuking the out-of-date term from public consciousness, as Blizzard had already started moving away from it in the past few months.
The change is purely cosmetic, and does not affect any functionality within the games or the launcher itself. The web URL still works, though.
The move make sense, as Battle.net is a relic of PC nostalgia before Blizzard started creating games for console and mobile. Identifying everything with the Blizzard moniker now ties everything into a neat little bundle that is understandable to new gamers who may not have known the significance of what Battle.net stood for previously.
The big question is if Blizzard charged itself for the name change and the cosmetic upgrade.