Sicilian defense question

Playing the old sicilian (1. e4 c5 2. Nf3 Nc6), what's the best continuation for 3. Bb5, my specific question is if we should take away the knigth, or continue with any other move i.e. Nf6, I'm taling in case of Bxc6 it creates an isolated pawn, doesn't this suppose a little disadvantage?

After 1. e4 c5 2. Nf3 Nc6 3. Bb5 Nf6 4. Bxc6, ...bxc6 strengthens black's central control and opens the b-file for the rook, while dxc6 prevents black from having an isolated a-pawn and opens lines for the light-squared bishop. In addition, black has the bishop pair. I don't think this is anthing to worry too much about.

The most popular "book" move is e6 at that point.  :)

Shredder 12 puts it at +0.29. 

I personally like Nf6 here, just continuing development.  But d6, g6 and all kinds of other moves work here.