We're hearing from... well, let's call them "people familiar with the matter" that HTC's Thunderbolt -- a phone that's supposed to be Verizon's first with LTE -- is experiencing positively miserable battery life that's making it difficult for testers to avoid carrying a second phone around as a backup. How bad? Two to three hours from full to empty in some cases. Of course, we wouldn't be surprised if battery life was really bad with the LTE radio left on -- the EVO 4G wasn't much different at launch with WiMAX lit up -- but the word on the street is that the power situation is largely responsible for the delays we've been seeing. In fact, our source tells us the phone is currently working on its sixth retail delay at the moment. More on this situation as we get it.We've just heard from another trusted tipster that there's definitely a new firmware in the works to address battery life and signal issues (which -- you guessed it -- are interrelated). Thanks, HTC Kid!