Before proceeding anymore a few disclaimers:
>The metagame for X/Y is still forming, there's no guarantee which move will becom popular when. Like earlier, Boomburst Exploud/Chatot/Noivern were uncommon, but now they have become noticeably commoner.
>I depends on the tier, each tier has different popular moves, like Geomancy being popular in Ubers but almost non-existant in OU.
Most of this is personal opinion, which can vary from person to person.
Here we gooo:
Water: Hydro Pump/Surf/Scald/Aqua Jet
Poison: Toxic
Ground: Earthquake
Dark: Knock Off
Rock: Stealth Rock/Stone Edge
Dragon: Dragon Dance/Dragon Claw
Flying: Brave Bird/Roost/Tailwind (I think)
Electric: Thunder Wave/ Thunderbolt
Grass: Sleep Powder/Giga Drain/Leaf Storm
Ice: Ice Shard/Ice Beam
Fighting: Superpower/Drain Punch/Close Combat
Psychic: Psychic/Psyshock/Calm Mind
Fire: Will-O-Wisp/Flamethrower
Bug: Sticky Web/Bug Buzz
Ghost: Shadow Sneak/Shadow Ball/Shadow Claw
Steel: Bullet Punch/Iron Head
Fairy: Play Rough/Dazzling Gleam
Normal: Swords Dance/Baton Pass/Shell Smash/Extremespeed/Substitute/Wish/Protect
Source: Experience
Hope I helped!