I agree, this is definitely turning out to be a great cast of characters! 
I read the description of the first scene yesterday (since I figured I would see it in the first few minutes anyway), and once again, Pixar has done a ‘Murphy’s Law’ as their opener. I’ve mentioned this last Movie Night, a theory I have where Pixar characters have the habit of getting into increasingly dire situations as one particular scene progresses. As in, bad things just keep happening one after the other so relentlessly as to seem almost improbable, but it sort of makes sense at the same time. It’s frustrating, but so thrilling at the same time!
For examples of such ‘Murphy’s Law’ sequences:
The Pizza Planet scene in Toy Story 1
Flik toppling the food offering in A Bug’s Life
Woody’s rescue of Buzz from the yard sale in Toy Story 2
Sully trying to hide Boo after she first snuck through the door in Monsters Inc
Nemo’s first attempt at stopping the tank cleaner in Finding Nemo
The entire opening sequence (cat in a tree, robber, suicide jumper, Bomb Voyage, train crash) from The Incredibles
Lightning getting lost from Mack in Cars
Remy’s attempt to escape from the kitchen in Ratatouille
Wall-E and Eve’s transport of the plant to the holo-detector in Wall-E
[spoil]Carl and Russell’s rescue of Kevin[/spoil] in Up
Progressively bad events one after the other, something I don’t notice as often in other animated films for some reason. I would be like “Come on! This can’t get any worse!” and it usually does.
I think TS3 will be no exception. Which is good! We all like to see our heroes being pitted against the odds. 
this same scene was shown at D23 last night. it looked and sounded amazing to me. Anyone worried of them messing up this beloved franchise can rest assured. This could go down with the third Lord of the Rings movie as the best third film ever…