There are a few new design details that take some getting used to
According to The Independent, the "notch" atop the display where the True Depth front-facing camera system sits is a bit of an eyesore, at least at first:
"At first, it’s something that really dominates what you see. It takes a chunk out of the Home screen, for instance, which has consequences for the information revealed in the top line of the display, of which more in a moment.
Your eye is really drawn to it when you’re viewing a photo on the screen and you zoom in. Or when you’re using an app like 1Password, the excellent password saver that I literally could not manage without, which has been optimised for the new display shape. Or watching video, which you can choose to view letterboxed or full-screen, but for one notch.
And then, you suddenly realise after a few days’ use, you barely notice it, in fact viewing a photo at maximum magnification again emphasises how the display dominates the phone as the photo sneaks into the top corners."
The Verge agrees:
"Covering the entire surface of the phone with the screen has consequences. There’s no getting around the fact that some of the sensors, camera lenses, microphones and speakers need to be forward facing; Apple addresses that by lining them up on a blacked-out notch on the top of the screen—kind of the Area 51 of the new iPhone. (Conspiracy theorists note: When you take a screenshot, The Notch disappears!) It’s an aesthetic setback (what would Steve Jobs have said?), but you get used to it, like watching a play when someone with big hair is off-center in the row ahead of you—a tiny distraction in your peripheral vision that you eventually get past."
However, Techcrunch found the notch to be a non-issue:
"In use, I have to say, the notch is just zero problem for me. I don’t give a rat’s ass about it. I know I’ll probably catch heat but I’m not carrying water for Apple here. I think it is absolutely a compromise but, after using Face ID and the True Depth camera for other stuff, I am willing to deal with it."
The Verge also found the bulky "bump" of the rear-camera to be distracting, but only at first:
"The camera bump on the back is huge; a larger housing than the iPhone 8 Plus fitted onto a much smaller body and designed to draw attention to itself, especially on my white review unit. There are definitely going to be people who think it’s ugly, but it’s growing on me."