It's more a way to highlight something, like notifications in iOS but only when we update the app. I'm usually more in Mac than iOS so there are easily things I'm not up to speed on but you can't use a feature if you don't know about it so if we can highlight the improvements we make and bring it to the attention of more of our users that's a good thing I would think. I know the Message Centre isn't high volume - I imagine it more for pointing out "hey, you can save a Login from the iOS Safari Extension" or similar. If you enable auto app update on your iOS device you tend to lose track of what has been updated recently, I know I do anyway. This could represent quite a few people amongst our user base.
So I would say the manual on our site still has a place alongside our knowledgebase and when those aren't helping there is still the forums or questions or discussions.