Agree, Ethminer is still very lucrative although it looks like Nvidia hardware hit the memory controller limitation and can't go anywhere else, much like Cryptonote.
Look at lyra2v2. It's also a memory hard algorithm.
280x Sgminer opensource(200watt) 4MHASH
750ti Djm-34 (sp-mod) opensource (40watt) 5MHASH
It's like creating a etherum miner that does 35MHASH on the 750ti.
But the opensource is only doing 8MHASH...