Any of the five justices could've been the deciding vote. I can't imagine eight justices sitting around in anticipation for Alito to cast his vote.
Don't buy into MSM hooey.
Yes, they sat around in anticipation. They had heard the case earlier in the term and were deadlocked 4-4. They needed to break the tie, so once Alito got on the Court, they reheard the case (oral arguments were geared toward him) and he cast the deciding vote.