Shares of Netflix (NFLX) are surging in Thursday trading after the streaming video company reported subscriber numbers that soared in the first quarter. Netflix said it added nearly 4.9 million subscribers during the quarter, ending with 41.4 million U.S. subscribers and about 20.9 million in the rest of the world. Those numbers topped the company's own expectations. Netflix co-founder and CEO Reed Hastings attributed the company's continued growth to improved original content and the growth of Internet television around the world. Hastings said the rise of competitors like Dish's (DISH) Sling TV, Sony's (SNE) Vue and a potential bundle from Apple (AAPL) is drawing more people in to the Internet TV ecosystem.