Lifehacker covers an experiment which tried to compare the speed of different input methods. As you might have guessed, full-size keyboard wins.
Nobody should ever doubt the power of the full-size keyboard (+ touch-typing). It’s faster than pen and paper, and thus is faster than anything that imitates pen and paper. It’s faster than downsized keyboard (QWERTY smartphones and iPhones). It’s even faster than speaking into a speech-to-text application. And more accurate as well. And that will remain for some time to come – until brain-to-computer interfaces will go mainstream.