I don't care how you take notes. Use the computer, like I did today. Use paper and ink, like I did at the collaboration workshop last week. Take photographs, as I do when I travel. The main thing is, if you want to learn, take notes. Learning is not a passive act; it is an act of engagement, where you involve yourself physically and mentally, where you struggle to understand and integrate the material. Note-taking is your contribution to what is a two-way communication with the source of the learning. Maybe you'll review them again, maybe not. Keep your notes in good order, just in case. But the main this is, that you take them.