Commencement speeches are their own genre, one that I like. In a way they are no better than any other self-help truisms, but people who give such speeches seem to tend to pay more attention to the language in the advice, making the advice more clear and more true.
David Foster Wallace is one of my favorite writers now. I only really "discovered" him after his death. He was a care and clarity with words that make everything I've read of his compelling.
And this speech is worth reading also because Wallace tries to transcend the genre of commencement speech and talk about what many other speeches fail to address.
http://moreintelligentlife.com/story/david-foster-wallace-in-his-own-words
AT&T has done good work on their text-to-speech work.
This is a demo where you can type in a sentence or two and hear it 'spoken' by one of several voices.
It's surprisingly good, especially in comparison to what was available just a year ago. I can't tell if it's produced entirely via AM/RM/FM sythesis, or uses samples of human voice. Either way, try it out. You'll be hearing lots of it in the near future, in those automated telephone labyrinths, as well as radio and TV eventually.