There is a lot of controversy on the reviews because it lacks LTE. Apart from that, the only thing that this phone have that is not found in many other Android devices is the glass back. The HTC One X (lacks non-removable battery, no SD card slot) and the GNexus (no SD card slot) are famous devices that have this problems.
My point is that the "beauty" of the Android ecosystem is that you can choose between a lot of different designs and specs. The Nexus 4 have glass back, no LTE, no sd card slot and non-removable battery. Will it be more popular than the S3, that don't have any of this "problems"? I don't think so.
I am buying the Nexus 4 because I love the design, I love stock Android and there is no LTE in my country yet. I always really liked the iPhone design and hardware, but the OS and the locked ecosystem are deal breakers to me.