This is the same kind of confusing stuff as in the article. Give it to me straight: when I upgrade stable Firefox to version N, how many more weeks will I wait for a stable update to version N+1?
But if you're waiting for a feature that was just finished to get into stable, that time is faster. You will only have to wait for N+2 instead of N+3.
You could also think of the change like this: if you report a bug in the current release version, and someone fixes that bug in Nightly, the fix will end up in a new release 6 weeks faster than before.