Replaceable battery, after removing the trackpad to access the final set of cells. Not the easiest projecdure and still is going to result in users doing what they do today, handing the machine off to a technician rather than be able to change the batteries on their device themselves. What a fall from grace from the first unibody macbook, where you could remove the battery with no tools and five seconds of your time since they engineered a door with a latch. I guess we celebrate what small affordances we can get these days.
Those are changes that the majority of users wanted, but very few want a return to clunky pop-out batteries, even fewer in an era of 20-hour battery life.
