Carland is definitely not an overlay for Test Track. Where exactly would they be having a bridge over the outside loops at Test Track? However, if you do look at the concept art, first of all the cars are identical to Test Track cars--two rows of three guests each. The track is banked like Test Track. The cars are blurring b/c they are going so fast...and the guests have their arms up in the air. This definitely isn't anything at WDSP. It's a Test Track-type ride. I'm just not sure where it would fit at DCA...and where the money would come from. Maybe this is John Lasseter's doing...I hope it ends up being a blended dark ride/thrill ride starting with some slower scenes showing off the various sets from the movie and ending with a high-speed race set to Rascal Flatts' version of "Life is a Highway" from the movie.
The nighttime show very well could be adapted for AK, but in the form shown in the pics, it's an obvious shoe-in for DCA.