It looks like MetroPCS' LTE network isn't going to be enough for it to continue adding subscribers at the same rate it has for the past few years — the carrier reported its Q1 2012 financials this week and was only able to add 131,654 net new customers. While that's a 90 percent increase over Q4 2011, the first quarter has been huge for MetroPCS over the last few years: the carrier added 725,945 net new customers in Q1 2011 (almost as much as national powerhouse AT&T added this quarter) and 691,602 net new subscribers in Q1 2010.

MetroPCS has been down year-over-year in net new subscribers for the last four quarters; combine that with Q1 results that are far off of the carrier's historical track and one has to wonder what the carrier will try next to turn things around. Not surprisingly, this hurt MetroPCS' bottom line — net income of $21 million was down 63 percent year-over-year. With T-Mobile and Sprint's aggressive marketing, relatively inexpensive plans, and bigger coverage footprints, it wouldn't surprise us to see MetroPCS continue to struggle.