Ed T: I think the "new model" is described in that link in a very simplistic way. The comment that it dispenses with the possibility of a "big crunch" is unnecessary, as the current models indicate that the universe is neither "open" nor "closed" but "flat".

This short clip goes into that at a layperson's level:

Laurence Krause Lecture Extract

It also answers to some extent HiLo's question about "what is between galaxies?". To elaborate a bit, galaxies tend to occur in clusters, and there is nothing much visible between these clusters. In fact, even within clusters, most galaxies are widely separated. But then we get into discussions on dark matter and dark energy.....