I need to be careful 'cause when I post anything about China the threads get taken out to a rice paddy and shot in the back of the head and buried!!!
That said, as someone who has worked in China for six months in the past three years with some folks involved in the talks I can tell you that getting pandas for DAK was on Iger's wish/negotiation/extortion list when dealing with the Central Government over SDL. BUT ... it wasn't exactly a priority ... not when compared with things like getting a Disney Channel in China (fail), more penetration for Disney theatrical releases (fail) and more govn't attention to fake Disney goods produced in the mainland (mostly fail).
I have no idea if DAK will see pandas, but my gut says it is likely at some point in the future.
As to their merits, well, they are beautiful creatures. But so are many others (like the ones slaughtered in Ohio after that crazy dude let them loose and offed himself!). They can be boring to look at as they tend to sleep a lot. I spent a lot of time watching them on their backs spread-eagled snoring at HK's Ocean Park.
The red pandas there (much smaller) tend to be much more active and playful and, frankly, excited me more because they ... well, moved around.
~GFC~