German site MobiFlip has noticed that the latest Nexus 4 devices have had a slight design change. It includes the addition of small bumps on the bottom of the phone to lift the device slightly off a surface, pretty useful as the previous version would sit completely flat, which also muffled the speaker.
The camera lens' outer ring is now also smaller. I can't really figure out why Google/LG made this decision, but it could purely be for aesthetic reasons.
I've also heard reports that many users have received the device with the tweaks, so it looks like this is legit.