I'll echo this concern. I'm running a Sony VAIO Duo 13 with a Core i7, which I specifically bought for its excellent battery life (8-10 hrs). I have Dropbox installed as well, which doesn't seem to impact battery life much at all, even with an extremely fast refresh/rescan rate (typically less than 30 sec). When I have BTSync running with a similar refresh rate, it kills the battery in around 4 hrs. Don't get me wrong, I love BTSync. It is certainly the direction I wanted sync services to go, rather than leaving sensitive data on an 3rd-party server somewhere. I love the new features of 2.0, but the battery issue is still a problem for me. I typically have to terminate BTSync when I'm not actively using it, just to conserve battery life. I hope power use optimization is still considered a priority issue for the developers.