Jan Chipchase is asking that question right now. In places like India and China some people sign up for classes on how to use their mobile device. It isn’t intuitive for them since I guess the technology revolution occurred so abruptly in areas like that.
Personally I learn the social way. I simply ask people. I google "Nokia E61 review" and see what turns up. Manuals are boring since they’re reference manuals, people however offer dynamic and interactive answers.
What really takes the cake is when I learn how to do something one way via person A, then another way via person B, and with all that knowledge I create my own unique algorithm for accomplishing a certain task.
The human mind is fascinating.
My best advice: never stop asking questions.