One thing that I've learned from musicians is that they perform a song over and over again. They don't just write it, sing it once, and then move on to the next song. But we do. As user experience practitioners, we tend to give a talk or write a paper, and then never give it again. Not very efficient, is it? It's like saying that just because I sang a song in California, no-one will want to hear it in Massachusetts. That's just not true.
I have given numerous talks on persona development at Sun, which prepared me for the talk I gave at CHI in April. Since returning from Italy, I've given that talk again, twice. Once, two weeks ago, at the Boston CHI monthly chapter meeting, and then again on Wednesday, at the Boston UPA Mini Conference on Usability and User Experience. I re-packaged it just slightly for the Boston CHI, and added 30 minutes of content for the mini UPA conference, but that same 10 - 15 minutes of material has gotten a good workout, as fas as talks go. I've also received two invitations to talk about persona development at local companies, so I may get even more mileage out of those slides.
Reduce, re-use, recycle ... words to live by.