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.
Well I woke up to being connected to tmobile band 4 inside my home instead of 3G.
Also connecting to band 12 at work inside the building which was just band 4 and 2 before. Still capped at 5 down and up but Loving this so far.