I'm still moderately excited for dual specs on my level 80 characters, it should be handy for switching between raids/instances and dailies. Cvarto of Proudmore began a thread about poor implementation about only allowing level 80 characters to use this feature. He fears that players will level as a single spec and have to relearn the other options for their class once they hit level 80.
GC's reasoning is that MMOs are overwhelming for new players to learn without working with two specializations. Cvarto contends that it still more difficult to learn a completely new aspect of the game, such as tanking, at level 80. I'd like to add that most players have little patience for inexperienced tanks and healers at max level.