well of course (well except that 1070 is cheaper then $500), but instead you put up with CF headache
its always been like that, SLI/CF is p/p value for raw power, but extra issues
like you can SLI 1070 (yeah its not exactly cheap, but still) and absolutely destroy both CF 480 and a single 1080 (and possibly still be on par or ahead of 1080Ti) and go straight into 4K@60+ territory .. but again you have to deal with that SLI
I am not a fan of SLI, or Xfire...
Up until just a few years ago, both were essentially a gimmick. Multi-gpu technology is improving and should be a serious consideration when building a rig today and forward. And remember, $400 is the cost of entry for CF'ing two 480s. But the new AMD 480 is an easy all-in-one pick, or choice for special builds.
HDMI and Display Port what..? DirectX12 what..? Vulkan what..? Power what..?
Those who can afford a 980ti, Titan, or 1080.. are not interested in mainstream cards. But those who a budget minded and building this holiday season, know later next year the can (if the need to) pick up another card and add more graphic power to their rig. Or if the get a bigger monitor, etc.
ie: Xfire and SLI marketing provide an easy way to slip things pass the wife, if you sneak one in 8 months later.
480 @ $199 ...?
I know my Titan's value just dropped today, and my 1 year old 980 might be replaced with something that has newer ports. It's just to easy not to buy a 480, even if to have just laying around.