Insurance Commissioner Steve Poizner's book"'Mount Pleasant" has hit the New York Times Bestseller list today, all but beating out his rival for California's coveted Gov. seat, Meg Whitman and her book "The Power of Many". Last night Poizner spent two hours with potential consitutuents at the Borders bookstore on Fair Oaks Blvd., signing autographed copies of his book, posing for pictures, and fielding questions from some folks who are still decidedly on the fence with regards to his candidacy. Poizner handled himself gracefully under fire, and with poise(pun intended). He was clear and concise, stating matter of factly what he envisions for the state and what his stance is on many of Cal