Control Priest is your best bet against aggro right now and overall strong deck right now, although needs some good skill to play correctly. There is no best deck, there are like 20 decks you can reach rank 10/5/legend with, its all about how good you are. But you can check Metastats website, lots of information down there gathered about current meta, successful decklists on particular ranks, how favored they are against other decks etc, great website and gets updated everyday.
Control Priest is your best bet against aggro right now and overall strong deck right now, although needs some good skill to play correctly. There is no best deck, there are like 20 decks you can reach rank 10/5/legend with, its all about how good you are. But you can check Metastats website, lots of information down there gathered about current meta, successful decklists on particular ranks, how favored they are against other decks etc, great website and gets updated everyday.