First of all, the answer to your question is "yes". Secondly, I think the inherent low-bandwidth nature of online communication, is going to make it hard to replace. Third, one aspect of conversations IRL, is that they are NOT taking place on the computer, where you work (for many jobs). This very fact, is important psychologically. The fact that any online alternative is taking place in the same medium (staring at a screen) as work, will make it difficult to avoid either: 1) too much distraction to get work done, or 2) too little "reason" to go there, to have spontaneous conversations

So, it sounds like I'm being very negative, but if you manage to find a way around these problems, it would be an impressive feat of both technology and psychology. Good luck!