I am assuming your spouse will be eligible for NATZ in May 2014. As soon as she becomes a USC she can notify the USCIS to change the category of your I-130 to the spouse of a USC. Your adjustment will then move forward.
I am also assuming that you initially entered the USA with inspection.
The other attorneys are correct ... it takes years and you may have to wait a few more.
Be careful with your words. Since your wife is a lawful permanent RESIDENT of the US ... she can't merely come to 'visit' the US ... this country must be the center of her life and livelihood .... known as her 'domicile'.
IF she isn't careful, they may cut up her greencard when she comes to the US on one of her trips.
Franco Capriotti - Senior Immigration Counsel
CAPRIOTTI INTERNATIONAL LAW
email@example.com -- 1-503-803-0055 -- www.capriotti.com
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IMMIGRATION LAW PROFESSOR for 10 years -- LEGAL DISCLAIMER: This answer is offered for informational purposes only. It does not constitute an attorney-client relationship.