I’ve written a piece on the same theme for the next issue of The New Atlantis.
[Update a few minutes later]
Bob’s focus is on how it changes getting to the moon and Mars. My piece is broader, on how it changes everything, and requires a complete rethinking of how we build spacecraft.
This is a pretty good description of the test program to date, but I think he’s mistaken about the engines for LEO. It wouldn’t make sense to put Merlins in it, because that would mean it would have to carry two different types of fuel.