This has several advantages.
1. Less stuff to carry around.
2. When it's done, it's done. No typing up the notes.
3. You can email the meeting notes to the client as you leave the building. When they arrive back at their desk, it's in their inbox. Trust me, this impresses clients.
The only problem is that I have to start every meeting with "Sorry, I'm not txting, I'm taking notes" which makes me sound like a wally.