If I-130 has been accepted what is next?

It will take about 4-7 months for the I-130 to be approved by the USCIS. T hen it will go to the National Visa Center for consular processing document gathering and will take about another 3-4 months for everything to be submitted to the NVC by you and your spouse and then the interview will be scheduled at the US Consulate in Montreal. If you are successful at the interview, you will be granted an immigrant visa to enter the US and upon entry you will be a permanent resident (the green card itself will arrive in the mail shortly thereafter)

National Benefits Center does not process I-130 petitions. The only place where your wife's petition can be processed is Vermont Service Center, which now issues decisions on the petitions filed on October 22, 2012. This gives you a reasonably close estimate of the time your wife's petition will be "in Initial Review". What exactly "in Initial Review" means is a closely guarded government secret. Us pedestrians cannot even be sure whether its a stage in the process or a place (mark that both words are capitalized); this information is given on a "need-to-know" basis, and only Armani-grade USCIS suits need to know. I strongly suspect that "in Initial Review" is a government-speak for "just sitting there in a pile waiting to be dealt with, whenever we might find time for it" ("we" being Marshall's-grade USCIS suits) Assuming that your wife did not make any mistakes in the paperwork and filed all the mandatory supporting documents, when your turn will come, the system will generate an approval of the petition and forward it to the National Visa Center of the U.S. Department of State. NVC will end your wife a letter asking for visa fees. After she pays the fees, a visa number will be generated for you, and the case will be sent over to the U.S. Consul General in Montreal, where it will sit until someone gets around to send you a summons for an interview. The letter will list all the documents you will be required to bring (police clearance certificate, medical examination and vaccinations report, etc.) Although it will not be listed in the interview notice, you will be expected to bring evidence that your marriage is real. Try to assemble documents and photographs showing the story of your courtship, engagement, wedding, and married life. Hotel receipts, airline tickets, restaurant charges on your credit cards, records of phone calls between the two of you, records of your wife's visits to Canada (immigration control stamps in her passport, etc.), your visits to the U.S., and your joint visits to third countries; receipt from Tiffany's for the ring, invoice from the catering company for the engagement banquet, etc, etc, etc. Get some people who know you well (close friends, parents) write affidavits attesting to your and your wife's commitment to each other. It will decrease odds of a denial if your wife can come with you for the interview.

The I130 will take about 6-7 months to get approved, once it is approved there are couple of other steps with the National Visa Center before an interview will be scheduled for you at the US Consulate in Canada to obtain an immigrant visa to come to the US as a spouse of a US citizen.