It seems to me that the field of large commercial aviation manufacture seems to be not only evolving, but perhaps showing signs of pending overcapacity in another decades' time.
There are of course, Boeing and Airbus fighting it out at the large end but also the RJ makers competing with their current portfolios but also expanding into the realm of A & B with their newer, larger offerings. Then there are the Chinese looming on the horizon with the homegrown model, ostensibly for the domestic market but anyone who believes that is naive to say the least. Then there is the FD 728/928. And the Russians; enormously clever and talented bureaus handicapped by the legacy of communism. Such will not always be the case, however. They are looking to re-invigorate their commercial aviation sector and seem to be willing to finally do what it takes to make it work.
And so; lots of potential market overlap & product duplication chasing a very finite market. Given the level of coporate rivalry/animosity and gov't interference that exists with 4 major players, what will happen when there are more? The potential commercial & political fallout could be huge or could be nothing and we could enter a new golden age of commercial aviation.
Yes, greatly oversimplified, but...Thought and comments?