Interesting article. The short of it is this: mainline churches are dying and the evangelical churches are, at least, dying much more slowly, holding steady, and maybe even growing.
Mainline are the more progressive/liberal and evangelical are the more traditional/conservative. Which means, in the future, if trends continue, liberals will not go to church and conservatives will run the thing - at least in its current form.
This is not a good trajectory for anyone but I'm more concerned with the liberal side of it, honestly. And it's another reason church has to change.