Several new theories have been developed based on Daft and Lengel's original framework. Kock argued that some of the hypotheses of media richness theory lack a scientific basis, and proposed an alternative theory - media naturalness theory - building on human evolution findings. Media naturalness theory hypothesizes that because face-to-face communication is the most "natural" method of communication, we should want our other communication methods to resemble face-to-face communication as closely as possible.[28] While media richness theory places mediums on a scale that range from low to high in richness and places face-to-face communication at the top of the scale, media naturalness theory thinks of face-to-face communication as the middle in a scale, and states that the further away one gets from face-to-face (either more or less rich), the more cognitive processing is required to comprehend a message.[29]
To help explain media richness and its application to new media, Media Synchronicity Theory was proposed. Media Synchronicity Theory states that each media has a set of specific abilities that enables it to more or less effectively communicate a message, and that every communication is composed of two processes: conveyance and convergence. These abilities include: transmission velocity, parallelism, symbol sets, rehearsability, and reaccessability.[21] Media richness is also related to adaptive structuration theory and social information processing theory, which explain the context around a communication that might have an impact on media choice.[29]
Channel expansion theory was proposed by Carlson and Zmud (1999) to explain the inconsistencies found in several empirical studies. In these studies, the results showed that managers would employ "leaner" media for tasks of high equivocality. Channel expansion theory suggested that individual's media choice has a lot to do with individual's experience with the medium itself, with the communicator and also with the topic. Thus it is possible that an individual’s experience with using a certain lean medium, will prompt that individual to use it for equivocal tasks[30]