It isn't even clear to me what is really changing or whether it matters... WhatsApp has had a feature they have been working on with Facebook for a while to allow Facebook business pages to maintain a presence on WhatsApp with a hosted client (something you might appreciate being useful for a lot of companies), and as far as I know this is just that.
> The move, the spokeswoman said, is part of a previously disclosed move to allow businesses to store and manage WhatsApp chats using Facebook's infrastructure. Users won't have to use WhatsApp to interact with the businesses and have the option of blocking the businesses. She said there will be no change in how WhatsApp shares provide[d] data with Facebook for non-business chats and account data.
> The move, the spokeswoman said, is part of a previously disclosed move to allow businesses to store and manage WhatsApp chats using Facebook's infrastructure. Users won't have to use WhatsApp to interact with the businesses and have the option of blocking the businesses. She said there will be no change in how WhatsApp shares provide[d] data with Facebook for non-business chats and account data.