Using the command: /entitydata @e[type=minecart,c=1] {Rotation:[0:0.0f,1:0.0f]} does not change the rotation of the minecart.
Using the command: /entitydata @e[type=minecart,c=1] {Rotation:[0:0.0f,1:0.0f]} does not change the rotation of the minecart.
Weird... the command works fine now, but it didn't a minute ago... huh.