Her particular dedication to humanitarian efforts such as AIDS research and fundraising helped elevate public awareness, way before it was popular to do so as a celebrity 'cause de jour'.
Also, her personal dedication to worthwhile causes and to her friends, is to be lauded. Regardless of how one may have felt about Michael Jackson, she stood by him defending him staunchly - even through those infamous court cases when others grew silent or condemned him. She was there. IMHO, MJ might not have deserved such an ally, but she remained undaunted.
She had more backbone and substance than most in Hollywood or anywhere else, for that matter.
In her day on the short list of 'hot mamas' that could act and were fascinating to watch, there was Marilyn Monroe, Natalie Wood, and Liz as far as Hollywood actors.