I've been leaning towards i5 2500k just because of price. The performance I've seen for gaming makes the i5 probably the better choice, but what about programming ( compiling, multiple IDEs open ) and other general activities? I am coming from a 5 year old desktop so anything will be an improvement
Like you say, the performance of the i7-2600k isn't enough for pay the additional price. THe i5-2500k is the winner against any AMD CPU and many of the i7-9xx line, plus use less power, produces less heat and run cooler.
The i5-2500k can give you all that you need, and more if you overclock it.
Depending on what you are compiling, your HDD will most probably bottleneck you before your CPU, as for multiple IDE, it will eat lots of RAM, but not a lot of CPU unless you can actually write code in all of them at the same time .
go for i7 2600k (317$)itz performance is equal to i7-980x which costs around 1000$
your post has no reasoning as to why he should get it, other than "its better than the last gen"
For what he wants, the i5 is the better option. As was stated by PsychoSaysDie, the i7 is only worth it for heavily threaded programs such as Handbrake (Video editing) or anything else that runs flat out for long periods that scales and responds well to increased core/thread counts. (The 980x outplays the 2600k here at clock for clock due to 6core/12threads).
Also what was forgotten, was the i7 has 2MB extra Cache, 6MB vs 8MB. But again, this doesn't give enough boost over the i5 to make the money worth it if you're not using the extra threads.
So although you've probably already bought your rig, for anyone else who visits looking for the same answers, the i5 is the one to go for unless you Encode lots of video, want insane bench results, use other highly threaded applications, or simply like/want/need the e-peen lol..