The source that I get is about Obama as writer. The article talks about he as a writer being really focus on the book that he writes. He always asks others to read about his book and asks for their feed back. His book just like a tale about himself, really attractive and the good selling result represent his success as a writer.
“Written at a time when Mr. Obama says he was thinking less about a career in politics than about simply writing a good book, it leaves an impression of candidness and authenticity that gives it much of its power.”
From here you can also tell he really like writing, and he trying to make himself be a good writer. In that way, he can also wins peoples’ heart and trusted by people.
resource: http://www.nytimes.com/2008/05/18/us/politics/18memoirs.html