Often when I talk to students about using Twitter, I find them disinterested... in fact, they often say, "I already use Facebook to post status updates." Other times, I will find that the student already uses Twitter, but he or she is not maximizing it. So, here is one more way to consider using Twitter - to build your Personal Learning Network.
Career Tipster is a resource full of really current job advice and explanations of the Personal Learning Network have been all over this blog. Basically, the idea is that you need to build knowledge in your field to become an expert and the best way to do this is to collect information from a large number of resources. There are many ways to do this such as maintaining contact with instructors and networking within your field, but Twitter is also a great way to pull a lot of information to one place.
I know when I am on Twitter, I am not telling people that I just "Grabbed coffee with Sally," but I am following experts on topics that interest me such as health and baking (hmmm, those are sort of contrary to each other, aren't they?). Anyway, check out this Career Tipster blog for more info on building your own PLN.