This is one of many Disney Park Character greenscreens we did for their site. We ran it through an After Effects green screen plug-in (Ultimatte or Keylight I forget which), then ended up taking up too much out, had to dupe the comp several times to fill in the hole from an agressive key, and render a rough. Then proceded to roto all the garbage out. Used a null to move some photoshopped clouds around, and a camera to fake the zoom. This job was split up between like 2 compositiors for a tight deadline. Anyways Disney, don't kill me for posting this, think of it as free advertising.
Got lots of good tips for greenscreen on Mograph.net check their tutorials section if you are interested. That site is a goldmine if you know how to search properly. The video edit was done by our good friend Logan who was freelancing for us. She's now in LA enjoying the sun out there.