It should be about conversations (or 'two-way symmetrical' dialogue in textbook speak). But there's something asymmetrical about how Twitter is so often used.
Perhaps the problem is with the concept of 'following'. By following a celebrity, or a publication or a brand, I'm signing up for an asymmetrical relationship with little prospect of it becoming an equal conversation (symmetry).
Students and other novices often struggle to find the right balance. Are their tweets suitable for the public domain, or would they be better on a more private social network? How to develop from a personal comment on my activity towards a contribution to a public discussion?
Here are two useful posts from US academics aimed at PR students: