Since this got bumped up, I'll chime in with my battery report with my estimated battery life given the data Windows has collected over 1.2 years of battery use. If you go to command prompt, you can type in "powercfg /batteryreport" to generate a file containing lots of stats about your battery. According to mine, given my usage of Internet Explorer, watching movies, and playing games on battery, I have an average full battery charge worth 6h45m which means that some days it's more and other days it's less than that.