6/8 GB memory is too little, 16/32 would be better :/. The price is ok-ish.
Gigaflops are largely unrelated measure of performance - if we were able to milk all gflops from current desktop CPUs, we could already render everything in real time.
The "can run x86, omgwtflol" is also more of a marketing advantage - you still need different binaries of your programs, because it does not have SSE (so you cannot directly runy ANY existing modern code with floating point operations). But binaries are produced by the compiler automatically, so I could in theory take corona and easily port it to PowerPC, ARM, smartphones, etc. What counts is the way you need to write the code to get acceptable speed. This is the reason GPU programming is hard. Even though you can write your programs with the same C++ syntax as when programming for CPU, you have to write it entirely differently. And I do not know how vast changes would be needed to milk the xeon phi ;).