Not having read any more than page 4 of this thread....
Take at look at
ark.intel.com. Look at the 3rd generation CPU's Apple used. Check their Max TDB, Price and Graphics. Now look at 4th generation. It doesn't look as if Intel produce Haswell CPU's that would fit the mini at the price point and graphics performance Apple require.
Look at the design of the mac mini... not too dissimilar from 1st generation Apple TV, and previous generations of time capsule and airport extreme. Now look at the current generation of the airport extreme, time capsule and the new mac pro. All small footprint obelisk like devices. The iMac has recently also been redesigned. You could say the retina MBP is a new design compared to the MBP. Could the lack of available CPU designs on Intel's part be an indicator of Apple giving the Mac mini an overhaul? And in the process it moves over to cheaper desktop parts and an optional GPU requested by so many. It's eventual design looking somewhere between an airport extreme and a mini Mac Pro?