I would be very surprised if Apple were drop the discrete GPU from the 2.3GHz 15" MBP during the expected 2014 minor refresh. The engineering costs are already sunk. I can only think of two scenarios where it might make sense:
- if MBPs were suffering problems from bad 750M chips (we would already know if it were the case, so we can rule it out)
- if Intel were to release updated Haswell chips suitable to replace the 4850HQ in the 2.3GHZ MBP with a chip with much improved graphics. However, that is the one Haswell chip used in a MBP for which Intel have already released a replacement (the 2.4GHz 4860HQ) and there is no great improvement in the graphics.
So, I'm confident that any minor refresh of the 2.3GHz 15" MBP in 2014 would continue to use the 750M.
- if MBPs were suffering problems from bad 750M chips (we would already know if it were the case, so we can rule it out)
- if Intel were to release updated Haswell chips suitable to replace the 4850HQ in the 2.3GHZ MBP with a chip with much improved graphics. However, that is the one Haswell chip used in a MBP for which Intel have already released a replacement (the 2.4GHz 4860HQ) and there is no great improvement in the graphics.
So, I'm confident that any minor refresh of the 2.3GHz 15" MBP in 2014 would continue to use the 750M.