Several complaints on the wow forums about XP from Dungeons. Some are bugs, others are real changes. Just posting them here for the benefit of the community.

LFD Bonus XP "Missing" - Per blue post on forums - they say it isn't gone, just that it has been rolled into the XP for the final boss.

LFD Bonus XP only once per week - BUG - Per the same blue post above, the text display says the bonus is only weekly, but is in fact every time you run it

No Completion XP Bonus for Dungeon when not using LFD - Apparently True - Several posters on forums confirming that a walk-in dungeon run grants no completion bonus - regardless of whether you are power leveling or not. If confirmed, and proven to NOT be a bug, I believe this would effectively end power leveling through dungeons.