V8.0 starts downloading tonight. Release will be gradual to make sure there aren't small regressions. Many car configs, many environments.— Elon Musk (@elonmusk) September 21, 2016
Version 8.0 is a big change from version 7.x, as we heard when the new software was undergoing beta testing over the summer. Today, Musk called 8.0, "a major overhaul on almost every level" and said that his, "favorite new feature is the always-on max temp control for keeping kids and pets safe from overheating." This is a way to stop the car from getting too hot (higher than 105 degrees Fahrenheit). A fully charged battery has enough juice to keep a car from overheating "for up to a year," Musk wrote, adding that it isn't always able to detect babies and pets.
Tesla keeps temp below 40C/105F by automatically venting cabin & turning on AC when needed. Can do this for up to a year on a full charge.— Elon Musk (@elonmusk) September 21, 2016
The next update, version 8.1, will also allow you to set a minimum temperature, to keep the car from getting too cold.