If you care about GPU performance, wait for Broadwell.
Intel have always been saying that:
2011 "if you want good performance, wait for ivy bridge"
2012 "if you want good performance, haswell will knock our socks off"
2013 " if you care about GPU performance, wait for broad well"
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The future is OpenCL, no matter how hard Nvidia fights it.
But someone will have to come forward and bring OpenCL up to the level of CUDA. That hasn't happened, but I'm glad there are companies like apple who are pushing for it.