Twitter is a great tool for group discussions. You can also use it to post a question to someone and then allow them to respond when they have time. Sort of like email but public so everyone can take advantage of your initiative and see the answer. This past semester, my professor monitored her Twitter answering questions amlost on demand. Many times I would post a question and get an immediate response. I really felt connected! Remember, you can only use 144 characters per tweet (post).
I think this quote from Twitter say it all:
“If you remember one thing after perusing this page, it should be this: reading Tweets and discovering new information whenever you check in on your Twitter timeline is where you’ll find the most value on Twitter. Some people find it useful to contribute their own Tweets, but the real magic of Twitter lies in absorbing real-time information that matters to you.”
http://support.twitter.com/groups/31-twitter-basics will provide all the information you need to become successful with Twitter.
