I've just been comparing the pictures on the configurator of the Mk7 GTD with the Mk7.5. I opened them both up side by side and compared front, side, rear and you can see the changes. Should look ok.
Then i looked at the interior shot (looking from between the two front seats at the dash). It could just be the illustration but it seems to me that:
1) The keyhole is missing on the glovebox
2) The piano black trim around various bits of the inside is gone (round the air vents, along the top of the glovebox door)
3) The "silver" trim and GTD logo on the steering wheel is gone, in fact the steering wheel looks altogether less chunky and sporting - the centre boss is different.
Not sure this is good news... looks like penny pinching
Haven't looked at the GTI and R to do the same comparison, but you can if you want to - use the "performance golf" vs "new golf" to see.
EDIT - if you look at the 7.5 R you see the same steering wheel, but the GTI picture shows one more like the Mk7. In fact, if you look at a SE Nav you see the same wheel there.... I think its just a graphics f*** up.
The interior still seems missing the piano/carbon black pieces tho