Pokemon already had a release date by the time that second Direct rolled around. For Smash, we have nothing more specific than 2014.
So yeah, the fact that we're getting a dedicated Smash Direct does not indicate anything new in regards to the launch date.
It's not about a Direct dedicated to announce a date. It's about when the game dedicated directs happen.
I'l post again my earlier comment:
Until now there was no game focused direct other than an announcement direct (1st Pokemon direct in Jan/Feb 2013, MH 4) or one close (maximum 1-2 months before) to the release (W101, NSMBU, Animal Crossing New Leaf, Pikmin 3, 2nd Pokemon Direct, 2nd MH4 direct). SSB4 was already "announced" at E3 2013. If this is a Direct just for more details, than it would be a really new thing.
All the game focused directs can be seen in this list, the cells are yellow.