I've tried the wifi image transfer to my Mac. You have to download Sonys wireless auto import tool (v1.2), do some initial setup and then you can send your files from the A7 menu to your Mac.
That works! After doing some transfers I thought that the Sony engineers have even been so clever to shut off the A7 after the file transfer. Wow!
Unfortunately, that was a little misconception. The camera is not really shut off - in reality it's crashed and completely unresponsive. Sometimes shuttting off/on doesn't bring it back to life, I had to remove the battery to reset the A7r.
Has someone tried this? Maybe I'm doing something wrong...