Ellen Stofan's presentation on a Discovery class Titan lake lander isn't among them. A friend has seen the presentation, so it was apparently made. Perhaps she didn't want it posted for competitive reasons. A Titan mission affordable in a Discovery budget would be a very strong competitor (assuming that the technical risk is acceptable.
You can go here to look at the presentations: http://gishbar.blogspot.com/2009/04/opag-spring-meeting-presentations.html
Or here to read Jason Perry's summary: http://www.lpi.usra.edu/opag/march09/presentations/