When patch 3.0.3 was released, players should have automatically unlearned talents that were no longer in the talent trees. Well, that process didn't completely work since some players were still receiving credit for talents that no longer exist in the trees, so Blizzard pushed a hotfix to correct the issue. Affected players will no longer receive credit for having these talents:
Warlock: Improved Lash of Pain
Warlock: Fel Stamina
Shaman: Totemic Mastery
Shaman: Improved Lightning Shield (Rank 3)
Paladin: Precision
Rogue: Fist Weapon Specialization
Priest: Shadow Focus (Ranks 4 and 5)