EB-2 India and China were the big movers, advancing from 11/1/2007 to 3/15/2008.
http://www.usavisanow.com/visa-bulletin/visa-bulletin-dates-employment/
About the Visa Bulletin:
The Visa Bulletin is issued monthly by the State Department, usually between the 8th and 15th day each month and provides availability of visas on a per country basis and within each preference category.
Because the demand for green cards exceeds the supply, many foreign nationals, especially those born in India and China and to a lesser degree Mexico and Philippines, have to wait in line until an immigrant visa is available.
The following factors determine how long a foreign national must wait in line to get a green card:
(1) The visa availability for the foreign national’s preference category (example: Eb-2, EB-3);
(2) The country to which the foreign national’s visa will be charged, which is usually the country of birth; and,
(3) The foreign national’s priority date (the date that the PERM was filed, or if no PERM was filed the date that the I-140 was filed).