I never chipped my 7.3 because I was afraid the tranny couldn't take it.
The 6.0 is rated at 325 hp and 550 ft/lbs torque. It has a lot more power than my 2000 7.3 had. The new torqshift transmission is said to be equal or better than the allison. I guess I'll find out fairly soon.
they redesigned the torque converter, and they gave it a larger pump to help with overheating. It also has a tow/haul mode similar to the allison. basically if you hit the brakes in tow/haul mode it downshifts one or two gears gear depending on the situation.
I never had any problems with my 7.3 or tranny, so I'm hoping for more of the same.