It's not more content, they are taking the content that used to come in 1 raid patch and removing all the non-raid stuff and moving it into smaller patches released a little earlier. So you get the same amount of content, just every 3-4 months instead of every 6-8 months. It's a good strategy, but by no means are they expending any extra effort than they ever did before (except during Vanilla which is the last time they worked hard to earn subscriptions).