What cracks my nut is this part: "Slides from a top-secret 2010 presentation published by The Guardian... "
Well if it was that top secret IMHO it will not leak or let alone publish in The Guardian or whatever newspaper.
Having said that, i don't want to discredit the validity of the article, because i know for sure that if a secret agency wants to get into your phone, house, car etc...with all their resources for sure they will succeed. So no worries! %uD83D%uDE03