I still pick Dan Henderson, Cung Le or Gegard Mousasi. Three choices that should be up there.
Henderson's only chance is to replicate his first round of their title fight in a rematch. Why? Because he's the first guy ever do win even a round with Anderson since he debuted in 2006. He'd have to grind out a boring decision and do what he did against Palhares: stick to the fucking gameplan and DON'T TRADE WITH SILVA.
Cung Le is such an unorthodox striker that I think he'd fare better than most think. He has a solid, solid chin. Plus, his speed and takedown defense are good should Silva try to switch up tactics. Le's main plus is that with his San Shou he can keep even some the best strikers/wrestlers at bay long enough to wear them down (see: Frank Shamrock).
Mousasi is my dark horse choice because he has the ground tools to mix it up with the best and he's good enough at other aspects of the game to avoid taking stiff strikes long enough to force a takedown (considering Silva's weakest point is his wrestling) and work from top position.
Whoever voted for Bisping is delusional. Michael couldn't even finish Leben after fifteen minutes of his best Lyoto impression. Anderson would have no power to fear, so he'd kill Bisping inside of two minutes. Lawler would need to hope for a miracle right hand to land as his standup is way too meat-and-potatoes to deal with a surgeon like Silva. The other choices are laughable to me. Okami might last a round, but it was only an illegal strike that saved his ass the first time. Granted, you could say that he's improved, but a victory over a past-his-prime Evan Tanner doesn't do much to solidify street cred. Franklin needs to get the fuck out of that weight class and remain gone, because as long as Anderson's wearing the gold, he'll never be more than runner up with a rearranged nose.