Tough call. Fortunately I drafted both late in my deepest (and heaviest $$$) league.
Gordon is a better play as long as he's in there. If you need a starter then next 2-4 weeks he's an excellent pickup. From all I've seen Faulk is going to be on the six side of 4-6 so that means four more games for Gordon. He is a solid start those 4 weeks but after that will head back to the FFL bench. If Gordon plays well he may still get modest carries (5-15) but Faulk will certainly get the bulk.
Shipp is not in such a good position in terms of instant contribution. The Cards play Baltimore this week so I wouldn't expect much. Even after that it would probably be best to leave him on your bench until you see how much he improves on Emmit's rushing totals. I think he'll end up being a solid start in a few weeks and right now I seriously doubt that Emmit will play another game this season, if not ever. That makes Shipp a good long term pickup. Shipp ran very well at the end of last season and I don't know of any changes to that massive OL so I don't see why he won't return to form.
Short run: Gordon all the way.
Long run: Shipp all the way.
I agree. Shipp is a guy you can probably count on for the rest of the year, but Gordon really good start for the next 4 games. Cards have a pretty hard schedule, so he is a pretty tough start, but he will get all the carries.