According to a report filed by ZDNet’s Mary Jo Foley, Microsoft and RIM could announce a new, free, hosted BlackBerry service as early as today. Citing anonymous sources close to the plans, the site reports that the two companies will collaborate to provide the cost-effective BlackBerry Enterprise Service to customers utilizing Microsoft’s hosted Exchange 2010 Online service. “RIM is only mobile OS that doesn’t use (Microsoft) ActiveSync-aware devices and has a separate device management platform – the BES environment,” said the site’s source. “Most large enterprise customers run a on premise [sic] BES server to get the advanced device management.” A Microsoft data sheet updated yesterday seems to confirm the free offering, but Microsoft has yet to publicly announce the program.