Joey, the answer is yes to the upgrade. I have both and would not choose to shoot video with my 7d if the mkiii is available. Please view Philip Bloom's excellent review of the 5d mkiii. He covers the reasons pretty clearly. Shows examples.
I have just taken the plunge and bought the Canon 5D MarkIII. Also buy the on camera Microphone for it if you want (Videomic Pro)by RODE. There's a bracket you can purchase so you can shoot with a flash and have the microphone attached along side the camera. I'm very pleased with the Canon 5D markIII since I just upgrade from the Canon 40D. That was a huge jump. All purchases were made at B&H Photo. Now, I'm trying to figure out why my video footage off the CF card into Sony Vegas Pro8 shows all black, but the footage shows in the Canon Image Browser EX. Any solutions?