Generally speaking MY05 is the partition line. The MOST set of equipment was rolled out to different car lines across several years. W211 was the first platform to get the MOST infotainment set starting in MY03. For TeleAid (Communications Platform), there is only one box, N112, used in the MOST equipment set so far. This is my understanding.
Website announcements has to trade off easy to read vs exact accuracy in getting the message out. So they opt for brevity in this case.
Has nothing to do with wiring in car except for which new component is required.
In principle yes, but they did take the chance and introduced a complete set of new equipment. This is partially due to MOST being an industry standard. So some parts are very similar to those offered on BMW, Audi, etc.
In contrast, D2B is a MB special. They were forced to change to MOST (started by BMW) simply due to economics. If they stayed with D2B, cost would go up simply due to lower volume. D2B would not support high data rate components such as remote LCD screens anyway.
The sad part is, component vendors will own the IP. In the end, car companies including MB will simply be integrator of IP owned by others. Already, KIA is buying similar cylinder liners and piston rings for their engines. New Bosch ECU at best will be exclusive to MB for a few years. The innovative folding roof of the SL/SLK are popping up on every other make almost.
My apologies, you were right. The N112 was revised to dual mode from the original analog only. Here is the identification method. The N112 box is marked also. I have the late '04 production R171 digital ready version.