Hillsbrad Foothills was radically changed in Cataclysm. A former grassy zone with World PvP between the Alliance town of Southshore and the Horde town of Tarren Mill, the Forsaken have taken over the zone after the Shattering. Southshore has been destroyed due to plague experiments, and toxic waste covers a lot of the zone. The zone has also merged with Alterac Mountains, where you’ll find a lot of Syndicate and ogres. Around Winter Veil, you’ll be sure to find the Abominable Greench being a huge nuisance. Players can also queue for Alterac Valley and pick up associated quests.
If you’ve completed the quests since the Shattering, you’ll notice a lot of new storylines in the area, inc. the series of quests that turns your character into a quest giver ordering NPCs around like Johnny Awesome.