I think there ARE some limitations in text-only communication (as in chat rooms) as a result of the lack of visual cues, but on the other hand I often am impressed at how well people do communicate in those environments. Of course, some people are more skilled and experienced than others. It's interesting that the lack of face-to-face contact often results in people being more direct and honest in expressing themselves, which counterbalances, at least partly (and maybe a great deal) what is lost in meaning as a result of the loss of visual/auditory cues.