Trek Domane, Specialized Roubaix, Cannondale Synapse, Giant Defy.... For $8k, your options are pretty wide. And I'm probably going to get some disagreement with this, but there really isn't that much difference between most carbon bikes in this category. They will each have a gimmick to differentiate from others, such as Trek's Isospeed or the Specialized's Futureshock.
I'd suggest going to several local bike shops and trying "Endurance" geometry bikes and get the one you like best. You really cannot buy a bad bike in that budget range.