I agree - You'd think that after announcing the Unification match that someone would have got off their ass and think to make a singular belt for the occasion. But , sadly, logic and creative thinking are amiss in the WWE.
I don't think there was ever any intention to keep the title unified forever. Remember, this is not the first time those belts were unified. The same thing happened back in 2001 when Jericho beat both The Rock and Stone Cold. If they really wanted to unify them permanently, there would already have been a new, official title.
I agree with PSOjedi. Got to remember they just revealed a new belt a year ago. Although I'm sure when they put out a new title, people will hate it and complain about how they change the belt every year.