I was wondering how magazines and companies get their 0 to 60 time for
automatics? For a manual, it's assumed the car is driven by a
professional who'll launch the car at an optimal RPM, possible
multiple times, and taking the best results.

Do they launch the automatic cars or just punch the gas?
To launch an automatic, put it in neutral, rev up and press the brake
as hard as possible. This gives more power to the power brakes. Put
the car in D and press the gas as much as possible without the car
moving. Then just release the brake and punch the gas. Not much
skill involved, but should gave a few tenths to the 0 to 60 time.

Also, do they use the Tiptronics to manually shift or rely on the
computer?