The following are a couple upcoming conferences that include identity and security tracks and lectures:

“The Experts” directory and identity conference in Las Vegas – March 22-25, 2009. Includes workshops on ILM, AD, ADFS, and so on:
http://www.tec2009.com/vegas/index.php

Tech Ed 2009 in Los Angeles, May 11-15 (they have a security and identity track):
https://www.msteched.com/teched/technical-tracks.aspx