Today, Verizon and HTC are going to begin rolling out Android 5.0 to the HTC One M7 on Verizon, you know the device that came out 6 months after the rest of the carriers. The update is to Android 5.0 Lollipop and not Android 5.1, unfortunately. Droid Life states that the update is a two-parter. And once the update is completely finished, it will be on 6.21.605.3. The changelog is also available, and for the most part, it's what you'd expect.
After the update is complete, users will be able to enjoy the new notification panel, as well as new quick settings. There's also a slightly new lock screen. Main difference is the way notifications are shown on the lock screen. You'll also get Smart Lock, which allows you to pair a Bluetooth or NFC device to your smartphone and have it stay unlocked for as long as it's connected to that device. Which is a pretty awesome feature actually. There's also a few other changes that have been made to the HTC One M7 on Lollipop. What's important to note here is that this does not include Sense 7, which is what launched on the HTC One M9 last month. Last we heard, that update should be rolling out sometime in August over in Europe, so it's likely to be even later here in the US.
If you have a HTC One M7 over on Verizon, head on into Settings > About Phone > System Updates > Check for Update and see if you can pull down that update to Lollipop. It's likely a pretty large update, so you'll want to be sure you are connected to WiFi, unless you are one of the lucky ones to have unlimited data still. According to the shots in the changelog of the HTC One M7, Verizon has on-screen buttons for the device. You might remember that the HTC One M7 has capacitive buttons. And only two at that. So hopefully that's just a Photoshop mistake and the update won't actually give you on-screen buttons, since those would be pretty redundant.