If you haven't seen it yet, this New York Times page offers a particularly easy way to follow Barack Obama's victory speech: Next to the video window, there is the text of the speech, and it automatically scrolls along as the speech proceeds. Above these two windows there is a timeline which shows where in the speech you are and what the topic of each passage is. Have a look:
Barack Obama's victory speech
The whole speech is somewhat over a quarter of an hour. I think it's worth listening to.
P.S.: And if you've got another ten minutes, listen to John McCain's concession speech (i.e., the speech where he admits defeat).