Doing a random heroic dungeon instead of a daily heroic quest sounds awesome. Plus an extra 5-man to run. Given the fact that it is possible to run a 5-man a second time with the random instance feature even if you already ran the instance that day; no more, "Sorry, I am saved.", in guild chat. Better yet no more quests to forget picking up or turning in, aside from the new raid weeklies.
Just yesterday I went to run culling of stratholme which was both the daily regular and heroic and noticed I was missing the quests just before we started killing the regular daily quest mobs. After we downed the timed boss I took the log run of shame back out to get the quest shared and then back in again to the last boss. What a patient PUG. :)
More accessibility to triumph badges will be nice as well since there are only a couple things I want with conquest badges and quite a few I want to get with triumph badges. Will make me feel better about buying heirlooms with conquest badges. Not that I felt too bad about it anyway, an heirloom item for an alt is a huge upgrade in comparison to a handful of stats on an 80 and I do enjoy my alts.
One thing I was looking forward too, but turned out to get implemented differently was the disenchant roll option. For guild runs I was hoping that disenchant rolls would be trumped by greed rolls, so people who can use the item would roll need/greed and the disenchanter and/or people who couldn't use the item could roll the disenchant option. A third level of roll was not to be though; disenchant rolls and greed rolls are competing against each other. This means that disenchanters in the guild are still going to have to pass and hang back and wait for everyone to roll or roll greed with the rest and make sure no one else rolled before disenchanting. I'm not even an enchanter in any of my raids and I was a little bummed.