I started doing some snooping around and I found two logical fixes.
1. Manual swap.
2. Check your TPS (Throttle position sensor).
My white prong was unplugged from the 3 prong harness.
Untitled by todd5854, on Flickr
I took a small flat-head and pushed it back into place, and I got my transmission responsiveness back.
Another thing to look at would be the adjustment of the TPS itself, you can move it +/- approx. 10 degrees. Mine was set in the center and I haven't had any complaints with that. I guess you could control how high or low the trans shifts.
There's a few things that could happen to this sensor and cause weird stuff to happen. My TPS went bad, and the car shifted at redline and stalled when I let go of the gas. I suppose if the white wire became dead it would start the random / lack of shifting problem.
Worth a shot. Cost me $0.00