Untrue. If you sell links, you may lose the displayed Pagerank score. There is little to no evidence that anything else happens. And the TBPR (ToolBar PageRank) is (by legal decision) 1st ammendment protected free speach. Meaning Google can display whatever they like
IMHO, if people make a living selling the displayed PageRank (as oppossed to anything "real", which we can't know anyway), and Google shorten the green gif, then really, all Google are doing is stopping people from benefitting from their trademark. Tne legal implications of doindg so to stop a competitor are of ourse questionable...
The craziness of all this is that, ironically, the fuss has been raised over TBPR, not anything 'real' like people's site's sufferring a loss ion traffic, by ae person who never thought TBPR was important anyway (Jill, You Go GIRL!!!! Good times... Good times...)
The only constant in SEO (some would say life) is change. If you bought/sold links, bank the cash and accept that times change, and take solice in teh fact that you benefitted for so long whilst others, who refused to take the short-term cash, struggled along.