The perils of predicting interest rates on New Year’s Eve. And more than marking the new year, tonight will also be the most expensive night to take an Uber. More on that. Plus, for nearly two decades, AirTran Airways has been the “scrappy” airline. It consistently did more with less, kept airfares in check, and thrived even when other airlines went bankrupt. AirTran flew for the final time Sunday night. It’s been a slow process merging with Southwest Airlines; almost five years now. So what will Southwest do to keep the AirTran-spirit alive?