Is there a weekly Justice/Valor Point cap? Or is there only the 4000 max. limit?
Otherwise I think it's a mistake to keep the daily heroic dungeon for 75 Valor Points in Cataclysm. You raid T11 for Valor Points then T12 comes and all your points are converted to Justice Points you don't need and you can go farm daily heroics again. Especially if you don't have a solid income of Valor Points from raiding.
I almost thought Blizzard also thought that this is bad game design but apparently not. They could have better extended the weekly raid so you would get double the Valor Points from it and you kill twice as much bosses. Seems to me that that is more fun than going back to 5 mans.