I don't understand. An inputTextArea control should reference a text (String) property in a backing bean via its "value=" attribute. As long as the form submit passed validation, the property's "set" method will be invoked to automatically update the text in the backing bean.
If you're looking for something like HTML formatting, inputTextArea is based on the HTML TEXTAREA control, which doesn't support rich text formats. For that you'd need a specialized feature such as the RichFaces editor control, instead.
Customer surveys are for companies who didn't pay proper attention to begin with.