Steve thanks for the excellent review. With price drops on R9 290/290X/780Ti, I feel like the choice isn't as clear cut if you are stateside, especially for the 980.
NV side:
Gigabyte G1 970 = $370 MSRP Newegg
http://www.newegg.com/Product/Product.aspx?Item=N82E16814125684&cm_re=gtx_970-_-14-125-684-_-Product
PNY 780Ti 1.046Ghz + Borderlands = $400 Newegg
http://www.newegg.com/Product/Produ...&cm_re=gigabyte_gtx970-_-14-133-526-_-Product
Gigabyte G1 980 = $630 MSRP (!!!)
http://www.newegg.com/Product/Product.aspx?Item=N82E16814125682&cm_re=gtx_980-_-14-125-682-_-Product
At these prices the 780Ti is actually better than both of those cards since once 780Ti is overclocked to 1.2-1.25Ghz it will beat 970 and keep up with a 1.5Ghz 980 for $230 less.
As far as budget gamers, cards such as HIS IceQ2 290 = 290X in performance, fixes high temperatures and noise levels of reference 290 cards and can be had for $270, or $100 less than the 970 G1 card. If you pair up, you are going to save $200 and lose maybe 10% performance at higher resolutions. Plus XDMA engines make crossfire feel smoother than SLI in many games.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814161457&cm_re=r9_290X-_-14-161-457-_-Product
Either way, great choices for gamers but now that prices on 780Ti and R9 290 are settling, a $550-630 980 isn't so hot at all.
I also wanted to point out your comment that even a Core i7 is not worthwhile for games over i5 is not correct. There are several games where even a stock i7 4770K/4790K outperforms a maximum overclocked i5 4690K:
"We were aiming for uncompromised 1080p60 performance here, utilising top-end "very high" settings on both quality and textures, along with SMAA T2X anti-aliasing - the best form of post-processing available in the game. In an effort to take GPU bottlenecks out of the equation as best we could, we retained the services of the GTX 780 Ti. The end result is fascinating - while both chips perform well, the stock i5 is clearly the worst performer, with quite a few dips below 60fps during gameplay. Overclocking the i5 4690K to 4.6GHz improves matters significantly, but the stock i7 4790K clearly keeps the game at 60fps for longer and hands in the best experience overall." - Digital Foundry
http://www.eurogamer.net/articles/digitalfoundry-2014-core-i5-4690k-core-i7-4790k-review
And of course Ryse: Son of Rome where a stock 3.0Ghz 5960X has nearly 50% higher minimum FPS than an i7 4770K, with i5 4670K even farther behind:
http://gamegpu.ru/action-/-fps-/-tps/ryse-son-of-rome-test-gpu.html
Finally, there is BF4 multiplayer where i7 and FX9590 CPUs outperform Core i5 due to threading.
BF4 China Rising - i7 4770K has 31% higher minimums than i5 4670K, while a 3.5Ghz i7 3970X is nearly doubling the minimums of a 3.3Ghz i5 2500K:
http://gamegpu.ru/action-/-fps-/-tps/battlefield-4-china-rising-test-gpu.html
Therefore, while i5 4690K may be fine for 95% of games, I would recommend for 970 SLI / 290 crossfire owners (or future GM200) to get the i7 4790K.