This lets you off the hook for preparing an organized questionnaire. You can also conduct an interview. You ask the questions and take notes on the players' answers. I've done this very successfully using a hand held tape recorder. The tape lets you focus on listening rather than note-taking.
Verbal surveys have one distinct advantage over written ones in that they can be dynamic.
If an answer needs more details or opens up some interesting possibilities, you can choose to pursue that thread. Or, you can just move on to the next item. A conversation gives players instant feedback about their answers as well. They can see you nodding your head or frowning in puzzlement, and they are able to ask questions for clarification. This is an excellent method.