But Twitter users aren't usually broadcasting to hundreds or thousands of people - the mean number of "followers" on Twitter is apparently 70 and the median is somewhere between 11 and 25 (http://bit.ly/7ij0 - these are 2008 figures). That's a reasonable number of people to make up a social context.
The categorizations in that report are also a bit odd, it seems to me, restricting "tweets that try to engage followers in conversation" to "questions or polls." But surely that "inexplicable" post about sugar snap peas is as much an invitation to conversation (about sugar snap peas) as asking "Do you like sugar snap peas?" would be.
-- Voyou <voyou1 at gmail.com>