The project manager I am working with is convinced that Drupal can be used to develop a web application that allows user input and rating of the input. I don't see beyond the Content Management uSage of Drupal. I claim 100% ignorance. Can anyone point me in the direction of a tutorial or articles that can help me grasp how Drupal will work for the web application I desire to develop?
This is not the place to ask for tutorials. Exactly what you need depends entirely on what exactly you are trying to accomplish.
To answer your question in general, yes Drupal can be used to create any sort of web app you want, with the proper modules.
First, you should look through the modules page to show the expandability of Drupal and determine which modules you need to accomplish the desired effect. There are over 16000 modules available.