You have a good i7 with great amount of ram and good stuff ... Keep up with your system until socket 2011 boards and processor become less expensive (as the 1155 socket is right now).
It won't give you so much power upgrading to Ivy bridge, just a few pourcents. You should've buy a better graphic card considering that you play at 2560x1440 ... it will do it but you will need to change it again to keep up with the games at that resolution.
Overall, that PC can do one more year MAYBE 2 if the games don't get too developped.
Unless money is absolutely no object I would use that rig for now, crossfire with a second video card when the timing is right (price versus performance in games) and eventually just build a whole new rig. You mention that it's a gaming rig, yet your upgrade path is purely cpu/mobo/ram combos. While these will have some affect on your gaming performance I think you have lost sight of what your goal is. Only if gaming is a source of income for you and the extra few frames translate into tangible benefits would I reccommend those upgrades at this time.