There have been many miles of text written about how the removal of the portals in Dalaran and Shattrath is a terrible idea and it’s a waste of time travelling around, how Blizzard is evil and so on and so forth. So let’s step back and look at the travel within the newly broken world, ignoring for the moment flight paths and boat / zeppelin paths.
So we have the following routing for the Cataclysm / Vanilla zones. Stormwind and Ogrimmar are clearly the transport hubs, they have portals to get to all the new content, a clear route to get out to Outland and (if we look at the boat/zeps) a route into Northrend.
Looking at Northrend specifically there are some additional ways to get up into the Wrath content, but these are mostly open only to those who have completed it, or have gold to splash around on shiny rings.
The only weakness I’m seeing is access to TBC / Wrath content, but to be honest if you’re levelling then it’s unlikely that there will be much travel outside of those areas. With the addition of auction houses, trainers and the like there is no reason to travel back to your favourite “home” city, in fact prior to 4.0.3 it was essential to travel home to use the auction house or get trained. There simply was no option, training was a break in the levelling flow only made viable by the portals, this change actually makes more sense in that the toon questing through Outland and Northrend remains immersed in the zone fighting the expansion appropriate baddies, even though we know from the splash screen that Arthas has been kicked where it hurts and Bolvar has taken his place.
Nice security on that secret Tirion.
Enjoy the changes, mages get to make a bit of cash from their class perk. I doubt it’s going to be huge amounts, those offering the service on my realm are doing it for tips only.