Last month, at the excellent GlueCon conference, I gave a 30 minute version of my polyglot persistence talk. Here are the slides:
There is also a longer version of the talk as well as the source code the example application.
I listened to a number of great talks at GlueCon. My favorite was Confessions of a tech CEO who still loves to code by Lew Cirne of New Relic. Very inspiring!