I kept copious notes on Full Tilt because I tended to play the same games over and over again. If you are just putting random comments like DONK, or AGGRESSIVE, I am not sure they will be helpful at other tables (cash vs tourney, high vs low stakes, etc). I would much rather have hand histories and stats than my comments that I have left at any one particular time. The exception to this is people who I play against a lot, such as forum opponents, who I still take frequent notes on.