More data leaks..
So, you choose between Skype which still appears to have a quite reasonable record, or Google who has as yet to achieve any improvement in the way it mistreats privacy. Let's just give them a way to tap your conversations as well, then, shall we?
Oh, and spot the BS. The actual chart would be blab-bla-bla-world discovers VoIP, world standardises on on SIP, every sensible IM adds voice, Skype goes its own way - and adds video, Skype is slowly seeing the light, IMs catch up on the video thing, Google runs out of privacy things to violate, Google offers VoIP. That's a more honest presentation of "Google comes to the party rather late because maybe inventing a VoIP voice recognition and data tap was harder than it thought".
Exactly why is the NSA still getting paid?