First Video/Photo editing build - Need some help!

Hey all,

I've been browsing the forums for the last few months, and finally decided to join now that I've decided to build a new video editing PC.

My current desktop is a Dell 9150 circa-2006 with a few minor upgrades (upgraded from 1 to 2 GB of RAM and recently bumped it to 4), upgraded the power supply after the old one died, bumped the storage from 250GB to 1TB (2x 500GB), and a faster DVD burner. However, It's still using an older Pentium D, RAM is only DDR2 and at the MoBo's max, graphics are getting old, etc.

Anyways, here's what my new build's looking like:

CPU: Intel i7 3770K
Case: Antec 900
HDD: WD 1TB SATA HDD
GPU: GeForce GTX-650 GPU
PSU: Antec EarthWatts EA-650 PSU
RAM: G.SKILL Ripjaws X 16GB (2x8GB)
MoBo: ASRock Z77 Extreme-4 Full ATX MoBo
Blu-Ray: Lite-On iHBS212-08 Blu-Ray Burner
SSD: Crucial M4 128GB SATA SSD
Media Reader: Rosewill Card Reader
OS: Windows 8

The total comes to about $1300 after taxes, with the big ticket items being the CPU ($330), and the MoBo ($140). What do you guys think of this build, will it be a good performer for the price? Also, where would I be able to save a few bucks?

The PC would primarily be used for video and photo editing. My current machine takes about 5 minutes to render a 30 second 1080P clip in Premiere, and processing deep sky astrophotos can take up to an hour or more Don't even get me started on exporting...
I'd also be using it for some light (key work here is light) gaming, and would be used with multiple monitors, which is why I sprung for a graphics card above the cheapest model. is it still overkill? I know that Adobe implements some performance improvements with Nvidea GPUs, which is why I went for the GeForce. Any other recommendations?

Another concern of mine is the CPU, $330 is an awful lot, especially with the i5 almost $100 less. How much of a performance drop would I notice if I went i5 instead? Does the i7's hyperthreading really make that much of a difference?

So, what would you rank my build overall, where can I improve, and how could I save some cash? I'm planning on buying the parts in a few months, so in case that something new and better is released until then, this is what my build will be.

Thanks,
-Evan