Well, not nipped completely, but severely hampered. In the latest build of the Cataclysm beta, there are no longer portals back to the major Azerothian cities from both Shattrath and Dalaran - the two major hubs from the last two expansions. Why were the portals removed? According to Blizzard's community manager Zarhym:

"The reason the portals from Shattrath were not removed from Outland when Wrath of the Lich King released is that there was a new central hub with portals to all major cities in Northrend. There is no longer a neutral city hub which both factions will be using in Cataclysm. We want to ensure visiting the major faction capitals is still the most attractive thing to do in Cataclysm, rather than having people use Shattrath and Dalaran as easy connector hubs.

To make up for this, we'd like to add class trainers and Auctioneers in Shattrath and Dalaran for those leveling through The Burning Crusade and Wrath of the Lich King content."

I tend to agree, although it'll take some time to get used to the adjustment of having to travel around Azeroth again instead of an easy Hearth + Portal combo to get to any major city you want. What I find a bit ironic is Blizzard's reason for not putting Auctioneers and class trainers in Shattrath and Dalaran in the past was because they still wanted the old world Azeroth cities to remain somewhat inhabited. Now they still want the main Azeroth faction cities inhabited, but they're adding Auctioneers and class trainers to drive people out, in a way. Funny how things change...

Note that other portals, such as those in the major cities to and from new Cataclysm leveling zones, will still remain in-game.