I can't speak directly to the Contemporary but, I had the Concierge at the Beach Club and it was awesome. Great food, perfect for breakfast on the go. We made a priority seating right from the hotel. I'm sure the concierge's at both resorts are comparable.
I didn't like the fact that we never saw the same one twice. Some were helpful and deserved thanks. Others were liars and needed chastising. But, the food is well worth it.
Contemporary 12th (Technicaly Now 10th...) Floor Concierge Guarantees You a Renovated Room, which is worth it if you want one of the new rooms and snacks, but not much else. Contemporary 14th floor Concierge is Definatly worth it, as it is in all Disney Deluxe Hotels\Resorts.