IIRC, one of the developer interviews specifically mentioned that most of the new moves and such will be restricted to new Pokemon (such as Refrigerate, Parting Shot, Gale Wings, Grass Pelt, Strong Jaw, Gooey, Magician, Bulletproof, Boomburst, Freeze-Dry, Forest's Curse, Trick-or-Treat, starter moves, Noble Roar, etc).
I'd imagine they'll get wider distribution in the next game, when the newness factor wears off.
I managed to have Heliolisk teach Mareep Eerie Impulse as an egg move, so hopefully, some of the new moves that are actually good can be passed onto old Pokemon.