Emerging markets are out, frontier markets are in.That was the buzz at an exchange-traded funds conference sponsored by Index Publications and Financial Advisor Magazine in Palm Beach Gardens, Fla., last week. "Frontier markets" are countries on the "cutting edge of emerging markets," says Hernan Rodriguez, managing director at Bank of New York Mellon. He lists Nigeria, Egypt, Kazakhstan, Jordan, Ghana and Kenya, among others. In a similar vein, acronyms like EAFE (Europe, Australasia, Far East) and BRIC (Brazil, Russia, India and China), are giving way to MENA, for the Mid East-New Africa region of the world. All of these markets returned more than 50% last year. Nigeria was the biggest winner, surging 115.3%, according to Standard & Poor's.