I laugh hardily when videos are made making fun of Twitter, I also roll my eyes when some make blanket statements of how anyone who uses the medium is headed toward brain mush and a spiritually zombedic state (my exaggeration of John Piper's comments). Simply because I and others like Twitter doesn't mean we are fueling the "fires of narcissism." The Twitter use of some might step over that unfortunate line, but the majority of people I know who actively use Twitter just want to be connected with others and vice versa.
A perfect, current example of the power of Twitter is the election and post-election activities in Iran. From here on the other side of the globe I've been able to view images and read comments from Iranians as they live, not merely report, what is happening. CNN stated this morning that the Iranian goverenment has banned foreign journalists from covering today's rally's. But Iranian citizen's are still able to share (for now) what is happening in 140 character bites, and I am able to empathize with them more because Twitter is allowing me to see and hear their words.
I hope that doesn't sound naracistic.
If you want to read some of what is happening in Iran via Twitter, from the Twitter page do a search for #iranelections or #GR88. The # is like a tag and allows you to find all Twitter comments that contain it and the phrase it is used with. Here is a site that gives some info on following things in Iran: CLICK HERE.