They pledged to never use it--their spokeswoman was on the record on 3/9 saying they had not.
From the linked article: “Whole Foods Market does not sell fresh or frozen meat containing pink slime,” Krauss said. “The majority of our ground beef is ground in our stores, from whole muscle meat.”
I guess the question is whether one can really trust a spokesperson, but I'd be interested in a link to the story you heard, Carol.