All major U.S. indices are trading slightly higher halfway through Wednesday's trading day. One lagging stock: General Mills, which is down significantly in midday trading.The Cheerio's cereal maker disappointed Wall Street by missing its fourth-quarter earnings.Barnes & Noble as well, missing its earnings. The story investors are watching though is the bookstore chain's spin off of its Nook business into a separate public company in an effort to boost shareholder value. Investors are welcoming the news, moving the stock much higher in today's trading. TheStreet's Susannah Lee has the details.