You mean with benchmarks like this
http://ppbm5.com/Benchmark5.html
Yes the 2600k is a wonderful cpu I am enjoying it. But would I choose it when I use my pc as making my daily bread? No. My wife got a 980x which I oc for her to 4.6Ghz. She uses it in her job where CS5 is just one of the applications. I tell you the 2600k getting spanked in CS5 due to the lower bandwidth. Traffick becomes just too heavy for its poor DMI. but my point is when time equals money and lets say the 990x beat the 2600k by 12-13 seconds per encoding or per job how many do you do a day, a month, a year. now calculate the money you saved by that 12 seconds. 600usd more price tag will look cheap and money well spent.
For using your system as a passtime like your avg work like gaming, lil bit of undressing celebs in Photoshop, audio processing etc etc then the 2600k looks excellent and the 990x will be a waste. That cpu wants a crap load of threads thrown at it not a couple
This is the 980x with my 3x gpus
http://3dmark.com/3dm11/517679
My 2600k score you'll find in my sig