This visa category is subject to numerical limits, which means that only a certain amount of visas are issued each year. As of the February 2-13 Visa Bulletin issued by the Department of State, individuals in this category that are eligible for permanent residence are those whose priority dates are earlier that October 2010. Therefore there is a waiting period of over two (2) years to obtain this visa. If you have been a permanent resident long enough to apply for citizenship (5 years) and meet the other requirements, this might be quicker. Once you are a citizen, your wife will be an immediate relative of a US citizen and not subject to the numerical limitations. In my experience, petitions by US citizens take significantly less than a year to process.
Answered on Jan 18th, 2013 at 1:54 PM