The article is BS and overblown. The talk itself was interesting.
The "find the name of the subscriber" bit has to do with the fact that a lot of carriers register the mobile phone subscribers name with the caller ID database. Since most cellphones don't use caller ID and only pair the number with their local address book, you wouldn't notice this unless the cellphone is calling your landline.
They demonstrated a technique to use a VOIP line to call another VOIP line spoofing the calling number (say 555-555-0001). They then harvested the caller ID info and moved onto the next number (555-555-0002), creating a massive database of number/name combinations.
Kind of like wardialing in reverse (cycling through source numbers not destinations).