BGR writes, Apple’s (AAPL) staggering success over the past few years can be attributed to the combination of several key factors. Great leadership is one, great products is another. Apple’s deep pockets and monstrous marketing budget have played an equal role in the company’s success but according to a new report, Apple may be losing its grip on an important demographic. Among teens, Apple is no longer cool. The news comes from the Buzz Marketing Group, an agency that specializes in youth marketing. Popularity is always a double-edged sword with teenagers and according to the sentiment observed by…