Sure, world PvP still exists to some extent, but I think Blizzard was having a harder and harder time defending their previous stance against allowing PvE to PvP transfers. Also, from a purely financial standpoint, the move makes great sense. Blizzard stands to make a pretty decent windfall of cash with this policy switch. Lots of players will want to try out a PvP server but may not want to re-roll a new character. Many will move to be with their friends and even more may make the switch out of sheer boredom and a desire to try something new. Also, let's not forget that Warhammer Online will be coming out soon, so Blizzard's timing may be more than a coincidence. It may also be a very astute business decision that will help them retain some long-time players who were on the fence about leaving for WAR.

While one still has to admire people who suffered through leveling up on a PvP server, I think this was a good policy change and it will end up being a huge win/win for both Blizzard and the players.