Are you 100% sure about the IMAX thing? Or are you basing that off what you had read elsewhere. I can totally understand why a lot of people would assume that IMAX Laser is used (e.g. the fact that IMAX Film was used previously, and the fact that Disney has said that the new projectors are digital and use lasers), but at least in DCA, I know for a fact that the projectors are from Christie. According to
@Alektronic the projectors in Epcot are also Christie, which would make sense since Disney would probably want to be consistent in quality across coasts if possible.