T-mobile is now updating the LG G3 on their network. Chances are that the Verizon LG G3 will be receiving an update pretty soon too. If you are rooted you will probably want to get your device back to stock before receiving an over the air update, especially if you have changed any of your system files. We still don't have a recovery. So if all you have done is root the device you may can get away with just unrooting it with the unroot option in the systemsu app.
Another reason you will want to grab the TOT file and the Flash Tool is just to have a safety net for when the bootloader is unlocked and we are able to begin flashing roms. Head to the link below to grab this stock file.
Via XDA