Since the Penguins are rebuilding and have 2 young goaltenders, there's no official #1.
Caron played more games last week, and since he played good, he might get the start again.
They are not contending, I don't think they are even trying to make the playoffs, I thnk their goal is to develop the youngsters and prepare the team for the post-lockout-CBA era. Fleury will be #1 next year though.