I really don't know what more they can do about DPS ques. There are always going to be more DPS than Tanks and Healers. They've already implemented a number of incentives to encourage more Tanks and Healers and it's not really fair to award more XP to DPS just because there is an over abundance of them. As many have mentioned, soloing PotD is a great asset for leveling. Once you unlock Beast Tribe dailies and Hunt Marks those also award large amounts of XP with far less time and effort required than dungeons. I leveled my WHM from 50 to 68 relatively quickly doing Beast Tribe dailies and daily Hunt Marks combined with the large amounts of XP awarded by completing the weekly Challenge Log tasks. There are literally millions of XP available outside of dungeons if you take advantage of them. Certainly plenty of stuff to keep a person stuck in a DPS que occupied until it pops.