I'll hold out on whatsapp until I can unlink "send this text to that number" from "here's a copy of my entire phone book"
I don't know how or why that was ever legal in the first place, and why Facebook and LinkedIn haven't been sued to death over it.
The contacts-matching system is how Facebook and LinkedIn'ss ultra-creepy "People you might know" list works, and I have no-doubt this will have led to things like journalists' confidential sources being discovered and harmful outing of closeted people, and worse.
Extra evil because you can be triangulated from the uploads of many naive people, so essentially they win in the end.