Today, at the Wells Fargo Securities Technology, Media, and Telecom Conference in New York City, Verizon's CFO, Fran Shammo, shared that Big Red's 4G LTE infrastructure will be finished with its rollout by the end of 2013. Here's a quote with a few more details,

Though Verizon had some issues with its LTE launch at the start, including the great service blackout of 2011, Shammo touted Verizon's reliability, citing the fact that Verizon's $3.9 billion buyout of nationwide AWS spectrum will give it an edge for at least five years. He added that Verizon will continue to look for opportunities to increase its spectrum in order to match demand, as about 250 million people utilize Verizon's LTE network, and the company hopes to increase that to at least 260 million by the end of the year. Verizon's LTE coverage should match the current 3G CMDA spread by the end of 2013.

Despite the company's push to increase its spectrum, Shammo mentioned that it will not be consolidating with other carriers or smaller competitors because that's not something that's likely to be approved by regulators.
Source: ArsTechnica