Why is this huge news??
Because without this mod, the MD-80 fleet would become extinct in 5 years, as we know it. (Not counting 3rd world countries).
Seriously. This mod solidifies the longevity of McDonnell Douglas narrowbodies in America, which otherwise would continue to diminish. Think about this: You are not that far from truly ONLY seeing 737s and A320s in your domestic terminals...is that what you want? (save the RJs and decreasing 757s.)
Lastly, think from a historical perspective when considering the 75 year history of Douglas...
To anyone who appreciates history, nostalgia, Douglas or the MD twin design, this could not be better news.