For starters, MacRumors has reported that an internal Apple memo covers an "under investigation" problem where the set-up process doesn't connect to open Wi-Fi networks. That's a particularly big issue, because it means you can't activate the iPhone and finish moving into your new device, even if you have cell reception.
The memo states that there isn't an official fix, but it does recommend the unusual step of connecting the iPhone to a Mac or to a PC with iTunes installed to piggy-back off their internet connection instead of trying to connect to Wi-Fi directly. Users are then being told to disconnect from their desktop/laptop and try again on Wi-Fi, when hopefully it'll work properly. If it doesn't, all Apple can recommend is that you keep trying until it does work.
If you're receiving an iPhone 14 today, then the good news is there is a small update (iOS 16.0.1) that you can download during set-up that'll help with this problem. Although you may still have to tether to your Mac or PC in order to download it in the first place., it'll hopefully sort out the problem.
If the Wi-Fi issue wasn't enough for you, there's also an apparent problem with iMessage and FaceTime on the new iPhones, too. So even if you do manage to complete set-up, you may be afflicted with issues such as being unable to receive messages and calls, or iMessages being sent with the generic green bubbles to other iPhone users.
Apple Support (via 9to5Mac) has a post addressing this problem, which says users should make sure their phone is enabled for iMessage by checking their phone number has been properly selected for messaging. To do this, go to Settings -> Cellular, and then check that the right number's being used for messages by going to Settings -> Messages -> Send & Receive and then Settings -> FaceTime.
We didn't experience any Wi-Fi set-up or messaging/FaceTime issues during our reviews of the iPhone 14, iPhone 14 Pro or iPhone 14 Pro Max. However as more of the TG team receive these new iPhones, we'll be sure to update you if we come across these problems.
That could be some time away though, thanks to the reported iPhone 14 preorder delays. Preorders are now finished, but those delays are likely to impact users hoping to order one today, so be prepared for a long wait to try out new features such as the Dynamic Island or Action Mode video.
Next: Facing another issue with your new iPhone 14? Check out our guide on all the bugs and issues so far on the iPhone 14 and when to expect a fix for them.