For general photography I just record the dates and such. When I'm testing/learning/experimenting I will record exposure, developer, etc., but that is just to guide me until I work out how to do something (or how I like something).

For example, I'm experimenting with some different B&W films, and have been keeping copious notes. These notes are used for each subsequent "session," to zero in on what works for me. When I have decided what I like, I will have worked out some general guidelines for myself to follow in the future, and further notes will not be as necessary. For me, the records are mostly useful within the process itself. By the time I'm comfortable with something, the information has been internalized.