Sony has posted what they call "PS4: The Ultimate FAQ," and it's pretty ultimate with 160 questions on it. That's a lot of them. You can look at it yourself here, but below I'll be posting the answers I think are most relevant to help cut through the fat.
What entertainment services will be offered at the launch of PS4?
Sony Network Entertainment’s Music Unlimited and Video Unlimited will be available at launch in North America. We will announce other entertainment services that will be available on Day 1 before launch. Check PlayStation.Blog and PlayStation social channels for further news and updates.
How do PS4’s parental controls work? Can I block Internet access? Can I limit the amount of time my child is permitted to use the console?
You can restrict start-up of the web browser, but you cannot limit the amount of time your child is permitted to use PS4.
What network services will be free on PS4, without a PlayStation Plus membership?
Some of the features users can enjoy for free include:
Accessing entertainment, film, and TV services (Users must subscribe separately to individual services)
Share options, including sending gameplay video and screenshots to Facebook, screenshots to Twitter, or livestreaming gameplay via Ustream or Twitch
Sharing video to Facebook,
Playing PS4 games remotely using the PS Vita system (Remote Play)
Comparing Trophy data with other users
Sending and receiving text messages from other users
PlayStation Store access (users must pay to purchase premium content)
Live item, activity feeds on Dynamic Menu
Party (cross game voice chat)
PlayStation App services (on iOS/Android devices)
Will PS4 be able to automatically download system software updates?
Yes, system software updates will be automatically downloaded for all users.
Will PS4 be able to automatically download game patches?
Yes, all PS4 users will be able to automatically download and install game patches to their PS4. In addition, PlayStation Plus members will enjoy the ability to have those automatic downloads happen while the system is in standby mode.
Will users be able to connect an external hard drive to expand storage on PS4?
No, this feature is not supported on PS4.
Will PS4 support any 3D content, including stereoscopic 3D games?
Technically, PS4 supports 3D gameplay at launch in North America, though no launch titles are currently 3D compatible.
What if I’m not able to or don’t want to connect my PS4 system online [to download the day-on update that enables many features, including blu-ray and DVD movies]?
PS4 owners in North America can contact SCEA Consumer Services at (800) 345-7669 to request a Blu-ray activation disc that will be distributed via mail.
Will I be able to install system software update 1.50 via a USB drive?
Yes, you will be able to download the firmware to your PC and transfer it to PS4 using a USB memory stick. However, to use the USB method the first time you take PS4 out of the box and before installing system software update 1.50, you’ll need to enable safe mode. When PS4 is powered off, press and hold the Power Button for seven seconds to enter safe mode. Note: Users should only update using official files downloaded from PlayStation.com.