The Supreme Court has upheld an EEOC rule that allows employers to coordinate retiree health benefits with Medicare for those who turn 65.  The rule, in effect, allows employers to reduce retiree benefits when they hit 65.  AARP opposed the rule on the theory that it constituted unlawful age discrimination.

Here's an LA Times article with more detail, the Supreme Court's order denying certiorari, and the EEOC rule.