Will this build work? Possible Improvements?

That will work but what is it going to be used for? Gaming or productivity?

Switch out the caviar green to at least a blue or maybe even a black regardless of its use.

Very nice indeed. Just a couple of tweaks though, if you want performance then go for a Black Caviar instead of the Green as they are very slow, unless you're not worried about that and want to keep the electric bill down then the Green is ok. (Don't use a Green as the OS boot drive, it will take 5mins to boot)
My biggest recommendation is that you put a SSD boot drive in there, especially if it will be used for gaming. An 80GB would be ok but obviously 120GB or more would be better.
1866Mhz RAM isn't going to be noticeable over 1600Mhz RAM, you really won't be able to tell any difference so I would save a few pennies there for sure. Also if it's main purpose is gaming, 16GB won't make any difference in games over 8GB. 16GB is only going to benefit you if you're HD video editing or with huge photoshop projects.

Other than that, all seems good. Enjoy it man =)

It going to be used mainly for gaming, thanks for the suggestion, I'll look into changing the hard drive to a black

Right, as it is going to be used for gaming I would 100% recommend you get a SSD as your main drive. As I stated above with the RAM you chose, I would cut back a bit on that and go for 2x 4GB 1600Mhz to save a few £$£'s as you won't get any performance increase with 16GB not in games anyway. Then put that money saved towards a 120GB+ SSD as it will make gaming a much nicer and faster experience when it comes to install and load times.

Also get an i5 and use the extra money for a better GPU. Maybe a 670 if you can stretch

I'll take it on board and have a look into it, I was thinking of having the SSD but was told it wouldn't be of benefit.

SSD wont give you better FPS but it will make your whole system more responsive

Thanks everyone for their suggestions and advice, I've taken it onboard and have amended the component list to;

Bitfenix Colossus, Monilith Black Full Tower Performance Case Blue/Red Switchable LED USB 3.0 w/o PSU
Intel Core i7 3770K,1155, Ivy Bridge, Quad Core, 3.5GHz, 5 GT/s DMI, 650MHz GPU, 8MB Smart Cache, 35x Ratio, 77W,Retail
Asus P8Z77-V PRO, Intel Z77, S 1155, DDR3, SATA III - 6Gb/s, D-Sub (VGA)/ DisplayPort/ DVI-I/ HDMI, ATX
128GB SanDisk, 2.5" SSD, SATA III - 6Gb/s, MLC-Flash, Read 490MB/s, Write 350MB/s, 8000 IOPS Max.
Western Digital Caviar 2TB (7200 RPM) SATA 6GB/s 64MB 3.5 inch Internal Hard Drive - Black
2GB EVGA GTX 660 Ti Superclocked, 28nm, 6008MHz GDDR5, GPU 980MHz, Boost 1059MHz, Cores 1344, DVI, DP, HDMI +Free Games
Corsair CMZ8GX3M2A1600C9 8GB 1600MHz CL9 DDR3 Vengeance Memory Two Module Kit
750W Corsair Enthusiast Series 750TXV2, 85% Eff', 80 PLUS Bronze, SLI/CrossFire, EPS12V, Quiet Fan, ATX v2.31, PSU
Samsung SH-118AB/BEBE Black 18x SATA DVD ROM - OEM

What do you think?

Regards

All looks good pal, that's a very nice rig =)

If it's gaming then got to an i5 and get a gtx 670

There is a lot of overkill here. Primarily for gaming, go with the i5-3570k. Only a handful of games even utilize 4 core processors, much less the hyperthreading of the 3770. Your PSU is overkill, even with overclocking and single GPU, 620W will suffice. You case may look impressive, but I don't see how it can be good for airflow. If you really want to go full tower, then go with a HAF 932. Your GPU is weak for such an impressive rig, so with the money reapplied in different areas, you can go with a GTX 680.

PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: Intel Core i5-3570K 3.4GHz Quad-Core Processor ($219.99 @ Microcenter)
CPU Cooler: Cooler Master Hyper 212 Plus 76.8 CFM Sleeve Bearing CPU Cooler ($19.99 @ Newegg)
Motherboard: ASRock Z77 Extreme4 ATX LGA1155 Motherboard ($127.99 @ Amazon)
Memory: Corsair Vengeance 8GB (2 x 4GB) DDR3-1600 Memory ($47.99 @ Newegg)
Storage: Samsung 830 Series 128GB 2.5" Solid State Disk ($112.98 @ Newegg)
Storage: Seagate Barracuda 2TB 3.5" 7200RPM Internal Hard Drive ($109.99 @ Amazon)
Video Card: EVGA GeForce GTX 670 2GB Video Card ($349.99 @ Newegg)
Case: Cooler Master HAF 932 Advanced ATX Full Tower Case ($119.99 @ Newegg)
Power Supply: SeaSonic 620W 80 PLUS Bronze Certified ATX12V / EPS12V Power Supply ($88.53 @ Amazon)
Total: $1184.44
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2013-01-09 08:38 EST-0500)

No need for a 680 when the 670 is so close for much less money.

Agreed that the 932 give awesome airflow and if your never going SLI then he's right about the PSU.

But no need for an i7 as I said.

Thanks Darth. Didn't realize how close they really were. You could easily get neck-and-neck specs with a good 670 OC.

OK, I've thought about your suggestions. I've decided to stick with my original choice of case.

I've changed the CPU to an Intel Core i5 3570K,1155, Ivy Bridge, Quad Core, 3.4GHz, 5 GT/s DMI, 650MHz GPU, 6MB Smart Cache, 34x Ratio, 77W, Retail which I hope will be good enough for a while for gaming.

I've also up'd the GPU to 2GB EVGA GTX 670, 28nm, PCIe 3.0 (x16), 6008MHz GDDR5, GPU 915MHz, Boost 980MHz, Cores 1344, DL DVI, DP, HDMI. Would this be a good investment?

I've also cut back on the PSU to 650W Corsair Pro Series Gold HX650 Modular PSU, 80 PLUS Gold, SLI/CrossFire, EPS 12V, ATX v2.31 +FREE Cable Kit, a lil more expensive than the Seasonic but its a gold standard.

Is there anything else I would need to change?

I would check your case to see what fans come with it. On a lot of cases the fans are optional, so just double check to make sure you do/don't need to buy extra fans. Seen this happen many times.

The case itself comes with 2x230mm fans and has 2 other bays for 140mm fans if necessary.

Sounds like an awesome build that should last a long time. Enjoy