I still think it was a mistake but the Sox are winning and playing very well so it's hard to make that argument very convincing (and plays more into my general belief that "managers don't matter all that much" so the win difference is miniscule, if it exists at all).
And aside from LaRussa being the right choice, how he was hired was pretty dodgy. The GM should make that call, and all other baseball-related calls, not ownership.