[Halius]

^^^

To add to Uteunayr's point the PoK books also took away a key ability for most Druids and Wizards to make money. I mean a lot of people make druid alts just so they can port others around, make some cash, and help friends. Add in the PoK books and you get much less need for a druid/wizard to port and ultimately you'll see less and less of these classes online. Granted they get new healing spells post-60 making them more effective priests but you take away one of their key roles which is porting.

Edit: I will also say that I did enjoy the PoP expansion and loved the Plane of Disease, Plane of Innovation, and other numerous zones it added on my warrior, just saying that it did take away a key role for porters.