weekly list is rather lengthy, I have a more difficult time compiling a list of things I could do daily, outside of the rep grinds and the like. I say could because if one were to do these things daily, there wouldn't be much time left for other activities. These activities require a high tolerance for boredom, as most of them involve low probabilities and drop rates.
Of course any achievement hunter will be slowly chipping away at achievements. This list isn't for those. This one is for those handful of things I'm after and could attempt daily, if afforded the time and the patience. At first glance, this list may seem short, but one could literally engage in some of these activities non-stop until the desired outcome is achieved. But eff that. Because pet battles.
Lost in the Deeps
Completing this quest ten times will award an achievement and companion pet. When I first came across this quest during Cata, I was sure I'd have the achievement well before we saw MoP. To date, I've completed this quest a total of three times. Given that the Pyrite Stonetender who provides the quest isn't guaranteed to offer the quest every day, it's taken me much longer than I anticipated. Between forgetting to check for the quest and checking for the quest only to find the NPC exclamation-markless, I'm hoping to knock this one out sometime before the next expansion.
Glop, Son of Glop
Players also get an achievement for completing this quest ten times, though no corresponding companion pet. Like Lost in the Deeps, the quest's NPC isn't guaranteed to offer this quest every day. Though I am an avid achievement seeker, this one makes WoW Daily mostly because it is offered in the same general area as Lost in the Deeps.
Reigns of the Vitreous Stone Drake
This mount drops off of Slabhide, the second boss found in the Stonecore. Neat thing about is that the mount drops on both normal and heroic, so it can be farmed. At 90, the fight is easily beatable with the Main, so I'm imagining most classes will be able to do it, too.
Reins of the Drake of the North Wind
Similar to the Vitreous Stone Drake, this mount drops in the Vortex Pinnacle off of Altairus in both normal and heroic versions. I have not yet attempted to solo this mount even though it's been on my list for quite some time.
I've spent more time trying for this mount than I care to relate. The introduction of AoE looting has made farming this drop from Lord Aurius Rivendare in Stratholme much less painful. The place is clearable in 5-7 minutes.