Top 3 still has to be some combination of CP3, Deron, and Nash, right?
I think Rondo has a legitimate claim to #4 at this point. I think that Chauncey, Westbrook, and Rose are all in that conversation, as well.
As for why Rose is sometimes listed in the top-3, it's because he led all PGs in scoring. I just don't think his assists are high enough to move him above a guy like Rondo.