Check out the $1000 Sept 2011 buildhttp://www.tomshardware.com/reviews/overclock-cpu-ssd,3027.html
You wont need the SSD so put the money towards getting an i7 CPU which is better for your type of work.
You could also scratch getting two GPUs and get one if you want to but if I'm correct 2 460s keep up with 1 560 but not too sure about that.
Also you will want more RAM cause I guess you will ahve a lot of program open at once, 8GB if your budget is tight 16GB if you can afford it.
You also wont need the CPU cooler so more money saved for you