Here's a pretty good video from GM High Tech and Performance Magazine showing how to properly use launch control on the Corvette ZR1 and Camaro ZL1:

How to & Demo of GM's Launch Control & No Lift Shift in a ZR1 Corvette and the ZL1 Camaro. We tested out the capabilities of the GM launch control & no lift shift on a modded ZR1 (15lbs pullies & full exhaust) and a stock ZL1 Camaro a while back and wanted to show you how it performed.

How To Use Launch Control on the Camaro ZL1 & Corvette ZR1 | VetteTube