The answer is because

1) india and china benefitted the last few years by using other countries unused visa quota. Now that other countries are starting to use their visas, there is less visas to spillover to india and china.

2) USCIS isn't supposed to spill over unused country visas until their fourth quarter (july to september). They made a very big mistake this summer (July 2005) when they ran out. Essentially, they used the spillover too early. They learned their lesson.

Therefore, they will wait to see how many eb2 140's will be filed by other countries during the first three quarters (fiscal year of 2006, start from OCT1) before they let india/china use the countries quotas.