Yes as they both are Haswell branded. But it would be better to get a 4690K as it has the same gaming performance as a 4790K. The i7 has hyper-threading which makes it's cores faster when video editing to improve video rendering times.
They don't have the same game perf in all games and with DX12 concentrating on threading etc we will see more threads become more important. In a cpu limited game you're going to see a difference, and almost all multi-threaded apps will enjoy the hyperthreading as you basically noted. It vastly improves the app types you mentioned and others (multipar, rar, ripping etc). As we get more games that have better threading they will separate.
If money isn't an issue why 4690? For ~$100 I'll take the chip that won't lose in anything in the future vs. 4690
Since the user didn't mention what he's doing, why talk him down from the best chip? If you can't afford it you wouldn't be asking about it right?
http://www.xbitlabs.com/articles/cpu/display/intel-haswell-refresh_4.html#sect0
Check out metro last light as an example of the game hit. 30fps is a lot right? 140fps for 4790 to 109fps for i5-4690. How many times would you like to see this in the future as they race to use more threads if you can just spend the cash now to fix it? Of course there are situations where you can tap out the gpu, but as we get better cards you'll be staring at your lacking cpu. Note even the old 4770 (also hyperthreaded) smokes the 4690 too. This user may have this cpu when we hit 14nm gpus (most likely will, unless they upgrade right and left). We will have gpus in 2-3yrs on 14nm and we haven't even seen 20nm which is about to hit. We will see many more cpu limited situations on 4 threads in the next 3yrs and it only gets worse beyond that. My next purchase will get me another 5yrs I hope so I'm always looking at threads now (current cpu 7yrs old...ROFL but admittedly I was waiting for broadwell after haswell wasn't worth much or I'd have jumped sooner).
I vote 4790!
I might say different if you were changing many components today (say a vid card too) when that $100 might be better spent. But not just in a cpu change when the user clearly has enough to pay for it or wouldn't mention it as the chip he/she is after. In apps you see the future of games as many pro apps are already where dx12 etc will take us in games. There are probably others limited by cpu also even today but unfortunately we don't get but a smattering of the same games on most sites and some of them not even great sellers (I personally believe you should only bench the top sellers, no point in benching a game that didn't sell a even 100K units+ Heck I'd say 1mil+). Thief is an oddball that hates anything but 4 threads (I'd say bad coding, but whatever) as they note. Even if the user said I only plan to game but still have the cash, I'd still vote 4790 with more threads just due to knowing what is coming in games.
Now if the user had said "but I'm cash strapped is there a better choice", I might say what you said or at least mention it as an alternative to save some cash. But this person could be a millionaire (probably not, but you get my point). We have no idea about the users finances other than they have enough to ONLY mention top end.