I'd like it to be open, but at the very least it HAS to be less privacy invasive than Skype. I'm not ditching skype for Google+ Hangouts or Facebook Messenger or something like that.
Honestly, I'd say Skype and Google Hangouts are equally invasive. In both cases, your conversation goes through $BIG_CORP's servers and gets data mined. That said, I would trust Google over Microsoft or Facebook - the latter will happily sell my data to other companies, but it's worth more to Google to keep it to themselves.
On a more practical note, I've found Google Hangouts to be the easiest to get working cross platform, and it has better audio/video quality than Skype too. I actually tried using XMPP/Jingle before this, but there are no good FOSS cross platform clients for it - you need to use different software under Windows and Linux, and good luck getting video to work under Windows. Hopefully someone will eventually write a WebRTC frontend for it to simplify things.