Most of you seem to think Ward is Cals biggest threat but stylistically it would be very similar to Hopkins v Calzaghe, where neither guy was actually prime but Joe's superior activity got him the win in an otherwise dire fight. Personally I think a prime Joe owuld beat a prime Ward because Ward does everything Hopkins could, just not as good.
Martinez moving up to fight Joe at 168 would be a great fight! Joe was never a big smw and loses out in terms of speed and power to Sergio. Plus Sergios awkward style would make it hard for Joe to not only land clean but do what he used to do so well, negate his oppositions strengths. I think Martinez is Joe's biggest threat.