At first, VoLTE will be used to deliver "Rich Communications Services" (which look like something similar to what Voice over IP/Video over IP outfits offer today) rather than completely replacing narrowband voice. It will be awhile before Verizon is willing to commit to that, due in part to LTE outages in late 2011.
On the flip side is MetroPC, which has pushed VoLTE as hard as it could.
Then there's Sprint, which will stick to voice over 1x for the foreseeable future, but routes Direct Connect over IP. Sprint's latest DC incarnation seems quite similar to one facet of RCS over LTE.
And one of sprints biggest markets which is New Jersey they do not have even close to uniform coverage or even contiguous coverage for that matter. Their overall coverage has improved but is still nowhere near T-Mobile is actual coverage. Along the highway where near where I live on for carriers work well because there’s a big cell site I say at least a couple hundred feet tall that services All for carriers But once you leave the main highway that runs through the east part of my town the coverage with the carriers does start to deteriorate.