I came to the same conclusion exactly two days after buying the Thunderbolt back in March. The LTE network is a game changer (when it isn't down). There were several LTE outages shortly after the Thunderbolt launch but most were fixed pretty quickly. I never lost 4G on the Bionic (or the wife's TB) yesterday.
I'm glad to see posts about this. I thought there might be some kind of outage, but it also crossed my mind that I was being throttled, haha. 4G was out in Cincinnati from about 6pm yesterday until? ??? It's back this morning, though.