After reading this thread, I rushed my rig to the dealership since my warranty is about to expire. Along with all the updates Paragon stated above, I also had them flush my tranny. Mine is a '03 with only 17k miles on it
Anyways, the result is definitely noticeable as far as the shifting point. It's now upshifting @ higher rpm, downshifting quicker, and smoother shifting all across. I don't know if it was the reprogramming or the flush but no doubt it drives much better now
The only downside is instead of an increase in mpg, i've noticed a decrease so far
I'll do some more driving to confirm this but regardless, it feels like a brand new truck