Ohana dinner is #1 now. (at least before 9pm or so) (as a note, Ohana is the most popular reservation for those who responded to the September ADR thread. I only know that as I was bored and created charts in Excel based off of the list that I'm keeping

)
CRT has been slightly easier for awhile (since they added princesses to dinner). It's still up there, but not nearly the crunch it used to be.
Le Cellier Lunch is up there, #2 or 3, dinner is a bit easier now since it's 2 credits.
Cali Grill around fireworks time is also up there (though earlier ones are a bit easier)
As mentioned, Tusker House pre-opening breakfast is right up there.
Chef Mickey's is still tough, especially earlier breakfasts.
And Fantasmic packages are also moving quickly, though if current trends hold, there will likely be more shows opened up closer to your travel date.