Hi Michelle,
I apologize for the delay! This wouldn't be possible with our built-in Action, and it looks like it's not quite possible with a workflow either. The problem with the workflow is that in order to populate information from the Form Fields, you'd have to run the workflow off the Posted Field's creation, not the Posted Form's, so you would have one Task for each different field.
I'm sorry for the trouble! Please let us know if you have questions.