If you are going all out on a beasting new system why cheap out on the GFX card? I would probably recommend the 9800GT from those two because it should be significantly faster and has that extra onboard RAM.
If you get driver issues you might want to swap out if the CAD card is validated for CS5. But REALLY, you should be rockin a much better GPU in that rig.
You should get a 2500K instead of a 2600K, as the performance will be similar (in graphics-heavy situations like yours, they'll be identical when they're throttled by the graphics card) and put the extra $100 toward a better GPU.
Also, get a cheaper motherboard, such as this perfectly good one (P8P67): http://www.newegg.com/Product/Product.aspx?Item=N82E168...
It's $50 cheaper than the one you picked, so that makes $150 toward a nicer card.
There's no reason to get 1866 RAM. Just get a $125 G. Skill 16gb 1333 set and put another $45 toward the graphics card for $195 total. You won't notice a difference.
So, with $195 plus whatever you're willing to spend (which should be a decent amount, no? You seem to like very expensive parts) you can get a beastin' graphics card. You can put in just $120 over whatever you wanted to spend before and get a 6970.
I see that your productivity is probably increased more with the CPU, and if you are doing lots of transcoding then the fast RAM might help too, but only if its coupled with an SSD. Otherwise you will just be waiting for the hard disk to read/write all the time.
Agreeing with kajabla though if you are running graphics intensive workloads on a multi-monitor (1920x1080 at a guess per 24" monitor) setup you really will benefit by saving on the MOBO (same brand, and are you really going to OC a work rig? if not why bother with the pricey one?)
Where I disagree with ^ is that you should probably choose an NVIDIA card for photoshop work as it has many functions that are accelerated with CUDA.
At least it is CUDA capable and has a pretty strong performance. (it was best in class for its time).
It will definitely run fine, but I suppose I am just thinking that with so much "horsepower" it is the weak link in the system. You have a race horse and then are putting a slightly overweight jockey on it's back and telling it to go fast.
I am sure however that you will be pleased with the performance of your system.