Silva's problem is that he started high and very dominant in the UFC, but didn't really improve since then. It's still the same aggressive Shogun-"overwhelm your opponent"-style with good enough ground game to not be afraif of take downs. But he still lacks intelligent pacing to not gas later in the fight and his style is too reckless to not get caught one in a while.
The question is what tactics will Brown adopt in the fight? Will he do what he did against Pyle or will he try and make it a cardio match. Either way though and whoever wins definitely a fight I'm looking forward to.