Taiwanstatus mentions the K2/K3. A minor point first, this is actually the K-3/K-4 visa. A K-2 visa is issued to the minor child of a K-1 (i.e., if an alien who is issued a K-1 in order to go to the States to marry an American citizen has a minor child, the child would be issued a K-2). Therefore, the new visa class mentioned by Taiwanstatus is the K-3/K-4. Applicability of the K-3/K-4 is summarized below:
To qualify for the new K nonimmigrant visa (known as the K3),the applicant for the visa must prove:
his/her marriage to a U.S. citizen is valid, and
he/she is the beneficiary of a petition (I-130) already filed with the US Immigration and Naturalization Service (INS) as the spouse of a U.S. citizen, but which petition has not yet been approved by INS, and
he/she is also the beneficiary of a special petition filed with and approved by INS in the United States, and
he/she wishes to enter the United States to await the approval of the I-130 petition by INS or the availability of an immigrant visa.
All four qualifications must be met before overseas processing of the request for the K visa can begin.
As noted above, all four conditions must be met before AIT would issue the K-3 (and, if the couple have a child, K-4 visas to their kids). Again, since AIT can accept and approve I-130 petitions I think most couples who qualify are better off just filing the I-130 with AIT. I believe most cases (particularly the case outlined by ckvw), falls into this category. I really don’t see any advantage for most couples going for the K-3.
The K-3/K-4 route would be more appropriate for posts where the consular section is not authorized to accept and approve petitions. At those posts, the petitioner must file the I-130 with the INS regional office nearest his/her residence in the States. After filing the visa petition, the couple then waits, and waits, and waits (you get the picture) until INS completes processing the petition. The K-3/K-4 visa class was created to cut down on family separation for those who had I-130 petitions in the INS pipeline, allowing those petitioned to be issued K-3/K-4 visas and then go on to join the American citizen spouse while waiting for INS to finish processing the I-130 visa petition.
Questions? Remember, window eight, third floor, Travel Services Section at AIT.