To be fair, Google still does a poor job of explaining the permissions apps declare in plain English. Thus, "Downloads files without notification" can make it seem like you have no control over what an app is doing, when all that's really happening is it's downloading information in the background. In Facebook's case, that's things like video previews (and now ads) in your timeline.
Not so scary after all, eh?
Other permissions Facebook took the time to explain are:
- Read your text messages: So Facebook can confirm your phone number via text message, if you've added it to your account.
- Read/write contacts: Lets you import and sync your phone's contacts, or sync your Facebook contacts back to your phone.
- Add/modify calendar events and send emails to guests without your knowledge: Facebook says it's just so that you can see your Facebook events in your phone's calendar.
- Rear calendar events plus confidential information: This lets the Facebook app check your calendar to see if you're already busy at that time when you're viewing a Facebook event.
All in all, nothing really scary there after all. Good on Facebook for finally taking the time to explain things.