Based on all of Tiny Voices input it seems he'd recommend something closer to this:
http://pcpartpicker.com/p/7jXzCJ
There are a few disadvantages with this recommended build. While it gets you the better gpu now, it comes with a weaker psu which cannot accomodate crossfire or sli later, it comes with higher cas timings at 9 vs 7 and a slightly weaker processor.
The advantages to my recommended builds are that you can upgrade the gpus significantly later either for sli or for a single stronger gpu with stronger overall components at the sacrifice of a better gpu currently but the 280 you wanted intially is included and is closer overall to your original build.
Both approaches are sound, it's up to you what you find fits best. I take nothing personal if you find tiny's recommendations to be a better fit! Have fun!