The one very good point of piece-mealing a build is that you can price-shop and pick deals; you're not in a hurry. An entire build means you get what you get within a few days of each order and if it's not a good deal, you still eat it and just buy at cost.
The Samsung 840 and OCZ Vector are trading blows on pricing and are the best SSD's you can get. Just picked up a 128G Vector for $120, just $10 more than the Crucial M4 you have picked out. Samsung is doing this too but both may stop as it's probably a roll-out marketing plan. Either way, this would be my first purchase. If you're using a spindle drive, it'll be an immediate difference even on older S/ATA ports that cap it's bandwidth. I still have a box with my first 60G SSD and it's way faster than even the 1TB WD Raptor (probably the fastest commercial spindle). My point being here is that any SSD will be good, old or not, and will be used in the end build. Video cards and all that other stuff evolve and can feel out of date pretty quickly. An awesome SSD today will still be pretty darn good when the build is complete. I bit on the 256G Vector lately, and I don't feel I'll want another SSD for some time now; I see it honestly keeping me happy for at least 5 years and I can't say that for any other part in my computer.
Depending on how you want to pace this build really clouds the rest of the parts. If the next part is around July, then you'd probably want to forgo the video card still and think about a foundation that is Haswell capable (this thread seems split, so I don't see what foundation you're coming from). If you have a SB or IB, forget this as most improvements I see are aimed at laptops and video card would really be better money spent. I don't see GTX660's dropping in price by July, but AMD units very well may pull out the stops to undercut nVidia's pricing in order to move parts.
I love Fractal cases and reviewers are just now starting to catch on to the new beast in town. However, you have to think about buying an ATX tower now days. So much can be done in mATX, we usually only have 2 drives, and I really can't think of a reason for a tower anymore. Heck, I just replaced the i7 Fractal Midi with an iTX and still very capable. No, I know you want a graphics card that's worth a damn to fit in there...but it goes to show that smaller can be just fine. Check out the SilverStone TJ08 mATX case. With just a single purchase of a mATX z77 board, I took everything from that giant and have it now in a shelf. IMO, in a world of the Fractal Node and $55 WHS, that's the place you stuff all your drives. Each desktop only needs one 2.5" SSD and nothing else. No WHS, cool...then buy just one 3TB drive to partner the %root% SSD.
So that's where the fork in the road exists IMO. You'll have to make the decision on which direction you really want to go. Do you need to have a big case or can you go smaller? Do you need an i7 or would a fast i3 do just as well in your usage? Do I need a lot of graphical performance for the monitor I have, or should I upgrade both? I'm so slow on saying you need a new graphics card because you just might not have the display size that calls for these new fancy cards. I just usually upgrade my monitor to find a fault in the ability to push all the new pixels before looking into new video cards. Three 23.6's are happy with 560Ti's, one 27" really wants the 660 in there. And I only buy Ti's for the idea that F@H will someday utilize all those cuda cores, so it's fine to ignore those for just gaming. We can give opinions until our fingers bleed, but it's still all in your head at what your end result will materialize as.
If you take our advice blindly, you could end up with a Johnny Cash Cadillac