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.
That very same crane from the previous page was used this past two days in Bloomington at a site off of 94th and Penn that has a Sprint site but the antenna on top of it is not (I thought it was T-Mobile), something horrible must have happened because they took the old antenna completely off the top of the mast and set it on the tarmac at the base of the antenna, replaced the RRUs, the cabinet was opened and literally everything inside it appeared to be replaced, then the antenna at the top was replaced by Monday morning and they were literally working all day sunday on it. The nearest I can think is the site above the Sprint antennas must have sustained lightning damage. I have never seen such extensive work on a cell site taking place on a sunday literally going from before 8 in the morning until well after 8 at night. I have extensive pictures. It appears the Sprint site was tangentially involved because there is still equipment and additional guy wiring in place and cabling going to parts of the site including the Sprint cabinets. Most curious to say the least. It almost looks like power was prevented from going to the site.