If I'm at my computer and taking notes, I will use notepad so I can store it as a text file. I can organize those however I wish.
If I'm in a classroom environment, I'll use my livescribe pen and paper because I'll know ahead of time about the training event.
If I'm caught by surprise walking about without my computer and need to jot something down, pen and paper is the only way. When I get back to the computer, I'll either scan it in using Neatworks or retype it into notepad. Or, if it's a temporary thing like a to-do list, I'll dispose/shred it once I've accomplished all the tasks.
I've been caught without any pen or paper so I've had to take notes with my android phone. I've taken pictures of white boards with the camera too.
I use the camera all the time when shopping around for the best price on merchandise. Take a picture of the product and price tag so when you go to the next place, you can confirm the model number and pricing of the previous place. I've had stores match prices that way too.
So, in summary, there's no easy answer except "it depends."