While there will no doubt be some major changes to every class come WoW Cataclysm, two huge changes were announced for both of the games "pet classes", and strangely enough these changes had absolutely nothing to do with their pets.
Warlocks
Warlocks will be receiving a major change as regards to their Soul Shards mechanic. The way it will work, is Warlocks will have three Soul Shards that are not items, but rather are used sort of like Death Knight Runes. They will be part of the User Interface. Using a Soul Shard is intended to be a big deal, either being used for a massive cooldown, or to power up the next spell the Warlock casts. These Soul Shards will regenerate when the Warlock leaves combat. Other ways to regenerate Soul Shards do exist, but haven't been announced.
Hunters
Hunters are going to be receiving a much needed change, along with their gear counterparts Enhancement Shamans. Instead of having Intellect and Mana, these two classes will instead use Focus, which will work almost exactly the same way as a Rogue's Energy. Through this Blizzard wants to get rid of long cooldowns on the Hunter's abilities, and streamline their gear set. Additionally their weapon ammo will be an item, not a consumable.
