What impresses me most is not its graphics performance but its well thought out approach to Heterogeneous Systems Architecture. AMD has been the prime driver in this area and Kaveri is, by far, the most complete solution.
I've been waiting for my Adaptiva Parallella Supercomputer board for more than a year and am loosing interest. A PC based on Kaveri would be a much more convenient platform to do some of what I was planning to do with the Parallella board.
It seems like a major advantage competitively for Intel and Haswell that Kaveri remains desktop-only....in spite of the cannibalization we're seeing in notebook sales these days, you have to figure mobile is still driving the notebook segment much more than the desktop market and that this is a problem for AMD until they can get notebook solutions as well as desktop ones.