As an academic, you're a professional expert. But sometimes you think, "But why does this take so long?" Bachelor's degree, graduate work, post docs more often than not. One answer may be because that it takes about ten years of hard study to become truly expert in anything, according to this article in Scientific American online.
That's the bad news. The good news seems to be that innate talent doesn't seem to be the deciding factor in developing expertise: continued study is.
On a somewhat related note, expertise -- not to mention passion and intelligence and lots of other good things -- are on glorious display at the TED website. The talks are wonderful, sometimes astonishing, must visit links. The blog has plenty of excellent tidbits as well.