I've never really seen it advertised. They definitely don't spend the kind of money Samsung do advertising the S3/4. Also, the hardware isn't all that nice looking when compared with the S3/4 or iPhone. It's very bulky in my opinion and looks are important to the average consumer.
I got one a few months ago (my first Android device) and I'm pretty happy with it but: the camera sucks, the screen is weak (I'm not sure the issue, it just looks a lot worse than the S3/4 and iPhone) and it's bulky. If I didn't need it for development purposes I wouldn't keep it for those three reasons. I'd probably go with an S3 if I were going to use Android everyday (although Touchwiz puts me off).
I've had a Nexus 4 for over a year and it's been passed around quite a bit between friends and coworkers who all either have iPhones or S3s and I've never heard a disparaging remark about the screen, quite the contrary actually.
The number one thing iPhone users lament about when they hold my phone is how bright and spacious the screen.
I've never once felt the camera sucked, in fact on a trip to Scotland with family I ditched my Canon PowerShot because the Nexus 4 was producing better results. The group consensus was that it took the best pictures on the trip beating out an iPhone 4S, Galaxy S3, two different Canon PowerShots and (shocker) an iPad.
I used the S3 quite a bit and I always come away feeling like it's a toy or one of those phones with giant numbers for the elderly. Samsung's UI tweaks feel like a throwback to UI design in Windows 95 or XP and the font sizes feel like they're geared towards old ladies. I always feel despite the screen size that things are cramped.
Physically speaking the iPhone windows out hands down by a large margin. The S3 just feels plastic, it's not really cheap but it's not nice either, the Nexus 4 feels much more solid in your hand and the choice of matte plastic appeals to me much more than the glossy of the S3. That being said it's build quality is dwarfed by the iPhone 4 and 5. It's sad that the beauty of those devices are hidden by the garish cases people always put them in because holding one naked is an experience.
It's interesting to hear your opinion. I exaggerated a bit regarding the camera - however my iPhone 5 camera is noticeably better.
My iPhone 5 screen is much better than the Nexus 4. It's much brighter. I find it hard to believe that iPhone users found the Nexus screen better. They might have appreciated the extra screen real estate but the brightness on mine is quite awful.
I would agree with you that the iPhone 5 has a better camera than the Nexus 4 but we're talking about camera phones, not a DSLR vs a Point-n-Shoot. It's better but it's not that much better. I'm sure my knowledge of exposure settings and basic rules of photography helped with my photos but they wouldn't have overcome the failings of a dramatically inferior camera.
Regarding the screen, Android's dynamic brightness adjustment setting is much dimmer than iOS's. In iOS you can define it to be brighter or dimmer while still keeping the dynamic adjustment, with Android the dynamic setting is either on or off. If you turn it off on both devices and set brightness to full, they're pretty on par. Colors looked warmer on the Nexus 4 when my gf and I compared the other night but neither screen was noticeably brighter.
That being said, Apple has the highest standards of quality in the industry so it's entirely possible that the quality of the Nexus 4's components varies wildly and I just happened to get a good one.
I got one a few months ago (my first Android device) and I'm pretty happy with it but: the camera sucks, the screen is weak (I'm not sure the issue, it just looks a lot worse than the S3/4 and iPhone) and it's bulky. If I didn't need it for development purposes I wouldn't keep it for those three reasons. I'd probably go with an S3 if I were going to use Android everyday (although Touchwiz puts me off).