The October Visa Bulletin from the Department of State's Visa Office notes that employment-based visa availability in the coming months is expected to be "Current" for the employment first preference (EB-1) category; the employment second preference (EB-2) Worldwide, Mexico, and Philippines categories; and the employment fourth and fifth categories. The Department noted that the estimates are subject to fluctuations in demand, but said that categories with a "Current" projection "will remain so for the foreseeable future."
For categories other than those noted above, the bulletin states:
China and India: The current cut-off date is approaching the most favorable date previously reached for applicants from China and India. The rapid forward movement is intended to generate demand based on new filings for adjustment of status at U.S. Citizenship and Immigration Services offices, which currently accounts for over 85% of all employment-based number use. Once the level of demand increases sufficiently, it may be necessary to slow or stop the cut-off movement, and a retrogression of the cut-offs at some point during the year is a distinct possibility.
Worldwide: up to one month
China: one to three weeks
India: up to two weeks
Mexico: up to one month
Philippines: up to one month
The October Visa Bulletin is available here.
The November Visa Bulletin is available here.