Ellis Hamburger for The Verge:

When you install Facebook Home (or buy an HTC First), your homescreen will be whatever your friends are posting, no matter how good, bad, or downright terrible. When you press the sleep button to unlock your device, these are the kinds of images that will come to life on-screen.

"What if our phones were designed around people, not apps?" Zuckerberg asked, but what if those people are ugly? What if you haven’t seen some of those people in five years? Yes, the News Feed you browse every day is filled with these same things, but your lock screen is the first thing you see in the morning and the last thing you see before you fall asleep.

Right—what happens when you don’t have a feed filled with photos from professional photographers? The Facebook Home UI looks great, and the animations are remarkable. But this is the sort of design that can look stunning in theory, and it might even look great for Facebook employees as they try it, but they are all outliers. The important question is, how would this design work for ordinary people? Judging by the content in my own News Feed right now—not that good.