Actually it is easier to state how many did not gain a new move
This list will be restricted to Pokemon that cannot learn TMs, or rather cannot learn moves unavailable otherwise by TM, as the new move Confide is available to every Pokemon that can learn TMs (except Burmy).
This List is as follows
- Caterpie
- Metapod
- Weedle
- Kakuna
- Magikarp
- Unown**
- Wynaut
- Wurmple
- Silicoon
- Cascoon
- Beldum
- Combee
- Kricketot**
- Burmy
- Tynamo**
The asterisked Pokemon have yet to be released for generation 6. Nonetheless, they are not likely to gain any new moves, with Unown having Hidden Power as its sole move since Generation 2, Tynamo, much like Beldum and Magikarp, has a purposefully limited movepool to contrast its powerful final evolution, and as such it is likely not to gain any new moves in X and Y. Finally, Kricketot, like the other Pokemon here, has a limited movepool that has not changed noticably since its introduction, and this pattern will likely continue. However, I wouldn't put it above Kricketot to learn confide, as it is a sound based move.
Technically, Smeargle and Ditto should be here as well, as they don't learn any new moves, stil only having Sketch and Transform respectively. However, these moves grant them the power to learn any move, and as such they have access to new moves.
Hope this helps
