Who was more of a "villain". Who was scarier. Who was more menacing. Who was more "real". Hands down it was Heath Ledger's Joker. That's gonna go down as one of the best movie villains of all time. Jack Nicholson was good. But there was no way to suspend disbelief. You knew Jack Nicholson's Joker could never happen. Ledger's version felt real. Creepy, but real.
I'm seriously pissed that Heath Ledger died. Cause now everyone's gonna think the praise is in part due to him being all dead and stuff, when really.. he was just that perfect in the role.