Well I've been using Twitter for several days now ... my initial impression is it is a potentially powerful knowledge sharing tool for those who can make full use of the application, i.e. those who can easily (and inexpensively) send and receive "tweets," particularly real time.
However as I've discovered in many countries, my home base Thailand being one of them, there is no way to receive SMS-based tweets on one's cellphone. It is possible using cellphone apps that take advantage of EDGE or similar data transfer protocols, but this introduces a different cost factor. After reading a bit I decided to install Twitteriffic on my iPhone, which has been easy to use and seems to be a decent application for tweeting. However, I have yet to decide I want to pay for a higher level of data transfers using my provider's EDGE service. This would be necessary if I use Twitteriffic very much.
My iPhone won't work at all from Japan next week, where I will be attending the IAALD-AFITA-WCCA World Congress. However, I will attempt to tweet from my laptop - I was inspired by Nancy White's tweets from a meeting in New Zealand this week. Just one more element of my own personal "Twitter trials".