I would guess it means he's definitely not doing any more catching this year, which would be a pretty big blow to any hopes of him being a primary catcher in the future. So if you're envisioning LH Buster Posey that dream probably dies with an ACL injury, but if you're envisioning deluxe Ryan Doumit that catches ~30 games a season, I'd say that's still obtainable even with a lost catching year.