Kaavya Viswanathan better steer clear of Oprah. Allegations that Viswanathan plagiarized parts of How Opal Mehta Got Kissed, Got Wild, and Got a Life have led to a recall of her debut novel. Little, Brown has asked retailers to stop selling the book and return their unsold copies. No word yet on whether Viswanathan will have to give back any of the half million dollars she received as an advance on a 2-book deal. Those......