Welcome! This looks pretty decent to me, although I would recommend a few changes here and there.
1) RAM. I have never even heard of Mushkin (EDIT: So I looked on Newegg and realized I have seen some of their stuff, but in the past 6 months or so, I have never seen anyone use them in their build, which may be telling. Up to you.), which is a bad sign. For RAM, since there isn't much of a price difference, always go with the more popular/trusted brands. Chances are nothing will go wrong, but it's not worth saving that extra $5-10 just for a brand that isn't as tested/known. Go with Corsair or GSkill.
2) PSU. While that is a pretty darn good PSU, I always advise going fully modular. Why? Because even if you use all the plug-ins on a non or partially-modular PSU (the one you have know is partially-modular) it is still way harder to manage cables, and even airflow may be affected (depending on your case). Find a modular PSU is all I would say.
3) Have you thought about what CPU cooler you will use? You will need an aftermarket cooler if you want to overclock, and if you don't want to overclock, it may not be worth getting the 'k' series i5. Just something to think about.
Yeah, it's very important to research your PSU thoroughly. Look at pictures, that's the best way to determine if it's fully modular or not. Granted you *could* do a build with a non or partially modular PSU (and many people do), I really think you will be thanking me down the road when you are building this thing, and you have a fully modular PSU.
nsouter... you're not serious about the accusation of Mushkin right? Many people use them in their rigs even though you may not see them. They have a proven track record and their ram is still one of the best even though nowadays all ram is pretty similar in performance.
As for the PSU, http://www.newegg.com/Product/Product.aspx?Item=N82E168...
Should you be referring to this one, it's is pretty much fully modular in my opinion. Not sure what's not "fully" modular there. I mean there is the obvious 24 pin and 8 pin MB power which is not modular because they are always needed, I don't see the problem.
Mushkin makes RAM just fine.. Really, you'd be hard pressed to find a "bad brand" for RAM.
As far as modular power supplies. I honestly don't see the point, unless you're either a super perfectionist when it comes to not having any extra wires, or you plan on using a computer case that has a clear panel. Modular power supplies more often than not cost more, and while one can argue that it makes wire management easier, so does buying a case that isn't a cheap piece of crap, competent cases will have good solutions for wire management (tie up points and space to stow the wires behind the motherboard, etc).
I would suggest spending the 30 bucks and get the 212 evo cooler now, even if you don't plan on overclocking right away, it removes the hassle of having to go back in later and remove the old cooler, clean off the thermal compound and install the new cooler. Save yourself a good half hour of unnecessary work.