But why is it front page news every time these guys pass gas?

Mostly because they're being very open about the development process on their blog, meaning you see stories about stages which wouldn't be announced publicly in comparable projects.

Setting up Plasma the way you like it can be very much like building a desktop from parts, albiet parts that are specifically designed to work with KDE. There are alternative taskbars, menus, clocks, launchers etc.

I have a vertical panel with various widgets, nothing but a picture on my desktop, and launchers and a directory (not~/Desktop) on the dashboard, for example. None of this is the default.

TFA actually says that it is a fork of the Gnome shell rather than the entirety of Gnome. Presumably, it would be built against and installed along with the official libraries and applications. Just a single component being replaced; a bit like changing the default browser to Firefox.