Right. This is one of those questions that seem to get asked on this forum every few days, and the answer is spelled out in the HHonors T&Cs, which are readily accessible at the bottom of
www.hiltonhhonors.com (via the link "HHonors Terms & Conditions") :
http://hhonors1.hilton.com/en_US/hh/...mbership_tiers
Effective January 1, 2009, members can earn and maintain VIP tier status based on stays, nights, or Base points earned in any calendar year.
Note that it says BASE points, NOT bonus points. (Bonus points are not base points!!!)