With that budget, my suggestion would be to use what you have now until Z68's come out. That way, you can get a cheapo 64GB SDD to use as cache, aka Rapid Storage Technology (PS and LR will love you for this), and a few 2TB HDD for RAID 1 or 5. Also, grab yourself a couple of nice IPS monitors if you must have multi-monitor setup. Otherwise, just one large (27-inches or more) one should do.
Good luck with your build and the photography!