The US State Department has posted the October Visa Bulletin. October 1st, of course, is the start of the new federal government fiscal year. Many employers keep October 1st in mind because it's a common start date for H-1B workers under cap-subject H-1B petitions. The date is also important in the greencard context because October 1st is when new visa numbers become available.
For the coming month, and the start of FY2013, employment-based first-preference (EB-1) processing remains current for all countries. In other words, visa numbers continue to be available for the processing of greencard applications based on petitions filed under the first-preference category.
The employment-based second-preference (EB-2) processing cut-off date advanced significantly to January 1, 2012, for all countries except China (mainland-born) and India. From July 2012 through and including September 2012, the EB-2 cut-off date for all countries other than China and India is indicated as January 1, 2009. Prior to July 2012, the date had been current.
For China and India, the "U" or "unavailable" indication that first appeared in the June 2012 Visa Bulletin for the EB-2 category has now been changed to July 15, 2007, for China, and to September 1, 2004, for India. This means that processing of greencard applications for citizens of the two countries in the EB-2 category can resume for those with a priority date earlier than the indicated cut-off dates. It also means that those within these categories who haven't yet filed their adjustment applications will want to be sure to do so next month, and the sooner the better. While the October EB-2 cut-off date for China is only about one month behind the date last indicated for China (in the May 2012 Visa Bulletin), the date for India is nearly 3 years behind the last-indicated date (also in the May 2012 Visa Bulletin).
In addition to EB-1 and EB-2 priority dates, the Visa Bulletin also contains information regarding greencard processing cut-off dates for the employment-based 3rd, 4th and 5th preference categories, as well as for other types of greencard filings.