(11-inch, to clarify) It seemed before when I tested my battery, my computer would read its % life going down pretty fast. I'd hit 90% (from 100%) in about 15 minutes. Which amounts to (if held true through the entire charge) a 2 hour and 30 minute battery lifespan. Now I've been testing again: - 35-40% brightness (switching between 5 & 6 bars brightness level) - backlit off - app store in background - constantly browsing - 1/3 of the time (exactly 10 minutes out of every 30 minutes) running a youtube video I get just under 12% battery discharge over 30 minutes (rounded to the nearest quarter percent I'd say about 11.75% based on watching the % drop and time move). 10% would be exactly 5 hours. Pretty decent. Overall I'm much more happy with the battery life. The battery life counter absolutely blows though. It's reading 5 hours and 23 minutes left on my battery, with 86% charge remaining. I know in a couple minutes it will likely drop down to 3 hours and 56 minutes, or something like that. Would anyone else like to share their battery life observations? Start from a certain percent (I started at 98%), and start at a certain given time, and record your battery life over say 30 minutes / 60 minutes / 120 minutes, etc, etc. I'm testing through right now (since I'm within a 2 week return period and just want to be 100% sure everything is proper... which it appears to be). I still wish they could manage to put the Macbook Air 13-inch battery into the 11-inch!!!