1. A method for simulating a run-time user interaction with a voice application, said method comprising the steps of: loading a user simulation script programmed to specify simulated voice interactions with the voice application; deriving from the voice application a nominal output, the nominal output including a text stream; processing the user simulation script to generate a simulated output for the voice application corresponding to the nominal output; calculating an execution time for the simulated output, the execution time being equal to a length of the text stream divided by an empirical speaking rate of a user; and executing the simulated output at its calculated execution time in conjunction with the voice application.