Well, if he goes up to a 2500k and z68, his money to spend on a video card will go down... may only be able to afford a 6850...
The OP should wait until he can push the budget. The 2500K isn't much more than the 2400 in the UK. [I know that he's in America - unless that's CAD or AUD].
Therefore it's only a little bit extra to spend.
Over the few years in which I've used computers, I've learnt my lesson about cutting my budget for cheap parts as well as not waiting until I can extend my budget for the parts that I do want.
Otherwise there will be more expenditure later. :/
For the OP: If you don't need the features of Z68, get a P67 B3 Revision board and then you'll give your budget more breathing space.