The Obama campaign said that he will "announce his Vice Presidential running mate via text message":http://ap.google.com/article/ALeqM5j-8g-0SMVRbSScyiKVhLBMgyYVAQD92GROV80. This is a great use of text messaging to engage constituents and demonstrate how a communication medium such as cellphones and texting can be used effectively in a campaign.
* It's timely (Supporters do not have to be in front of a television or browser to hear the announcement.)
* It's short (Unless the VP's name is longer than 160 characters.)
* It's opt-in (The campaign will actually have a way to connect with people directly)
(Hat tip to "the Vertical Response blog":http://blog.verticalresponse.com/verticalresponse_blog/2008/08/great-ema....)