does practice make perfect?

i've been reading (shocking, i know, who would have thought that i READ) a book called Outliers, by Malcom Gladwell. it makes the interesting proposition that to become truly 'proficient' in any skill, a person must spend roughly 10,000 hours practicing that skill. including novel writing.

BUT, i have to wonder, assuming that 10,000 hours is indeed the magic number, does reading count? what about writing for school classes or writing creative fiction that isn't a novel? how do you really measure the time one puts in to writing?

also, Gladwell completely dismisses the idea of natural talents that can achieve proficiency without putting in the time (10 k hours) practicing. however, i know of at least one famous person who appears to be evidence to the contrary.

what are your thoughts? is practice always necessary to make perfect, or do you think Gladwell is wrong? can other areas of reading and writing count as this 'practice'?