completely ignoring the theme, I think this could sell on the (cough! borrowed MMr technology.. cough!) alone. Seriously, between beaglebone running the whole thing on linux (cheap to replace, super reliable) and the reduction of wiring underneath, this should greatly reduce problems. Question is, will Stern pass that cost onto the consumers, or continue to raise prices?

I was thinking about this last night.. Could there be more to this than just reducing wiring and increasing reliability? There seems to be only a couple data cables coming from the backbox, and then 48vdc power supply.
If taking a playfield out only requires unplugging 3 connectors, could they be possibly allowing for a swappable populated playfield in the future? Imagine if instead of a vault edition, they create "the vault" system, not unlike what heighway pinball is doing. You buy a cabinet with the board/power supply installed, then buy your choice of populated playfield. Stern knows there are collectors out there who have simply run out of space (and not just buying Sterns, also the competition). That means selling off their old machines to make room, which potentially cuts into Stern's vault edition sales. Imagine if you as a collector invest in a "vault" cabinet, knowing you are simply going to buy the latest playfield. That reduces inventory of cabinets they have to stock, reduces shipping cost. Other than an extra 2 SKU's, I don't see why Stern wouldn't want to offer this (especially if they can upsell the playfield by itself).
Now I'm not saying this as a complete replacement, half of sales still go to operators, and I'm sure there are some people that want the original cabinet, but I can see this as a possible option.

Again, they could be paying for R&D. Any place that I've worked, usually you have to justify making changes through cost savings (to pay both for the tooling, and your salary to design those changes). The only way we can sometimes get away with it without lower cost is if a tool is getting worn out, so as long as they're paying for a new tool why not make some improvements. Stern is also not making millions of units like many big companies are, so making big changes like this has a bigger impact. Let's also not forget that Stern is moving into their new building soon, which I'm sure is costing a pretty penny to fix up, build multiple production lines, etc. That money has to come from somewhere. Not that Stern isn't doing well, but they are spending some serious money these days. My only hope is that all that investment eventually gets paid off so that they can lower costs, but nothing is going to drive them to do so unless sales go down, or the competition offers something comparable at a better price (which is very difficult from a volume standpoint).