So this just happened: https://github.com/ethereum-mining/ethminer/pull/18

Getting extra 2 mh/s on my GTX 1070, and reportedl the GTX 1060 sees even more improvement (see here: http://cryptomining-blog.com/8852-new-optimized-ethminer-for-nvidia-geforce-gtx-1060-gpus/)

Thing is I love mining Siacoin at the same time so I'm sticking with Claymore's for now, any chance these optimizations by David Li can be included in next version?