A 20-30% bump for the same price or possibly 7.7% more price is a bad deal? Strange...
Honestly, it is. We are talking here about something with a 700 USD/800 EUROs price right now. Granted, the value of money is different to various people, if you have enough them to burn, then probably it would be a good deal to you, even if the performance bump was 5 percent, just based on the fact its newest and fastest thing, which you want. To me, and majority people though around the world, as i suppose, its still quite a lot and difficult to justify to spend (when already owning 980Ti).
The reasons are simple. If you look at those gaming benchmarks, what are those cca 25 additional percent of performance bring to you? Something like Doom is now 125 FPS instead of 100 on 980Ti, what difference does that make? Unless very specific case, when 120FPS is some theoretical limit, you want to get over, cause of 120MHz display or VR, none. Ashes of Singularity is then 50FPS instead of 40 - once again, how does that even help? At 40 FPS, its already 10FPS above the 30FPS minimum, yet still 10FPS far away from at least 60FPS optimum....while its better, it does not really solve anything IMO.
And then some GPGPU performance, at those 125 percent of 980Ti, it would take me to render single picture cca 105 minutes instead of 2 hours (since at 200 percent of 980Ti it would take one hour). Under assumption thats 2 hours is the time needed to render that single pic. So i save 15 minutes. I need to render 8 pictures to save 2 hours. If i already own 980Ti (i dont), are those 2 hours of my life saved worth 800 EUROs? The answer is no, it would be, if only i produced those pictures en masse. Obviously in such case i would earn enough money to make the price more acceptable from my POV. But as you can see, even if the card is making you the money, its not that straight-forward YES!, thats good deal.
That said, as someone with gtx580 in my case right now, which i expect to be about 3x slower for my needs, i am probably gonna buy it. Unless some Titan coming already this year kind of rumors pop-up, which would make me reconsider.
My 2 cents.