Off the top of my head...
The top thing? Don't forget to smile. A smile is the handshake before the handshake.
Create an elevator pitch about yourself. This may or may not come out during your event, but its good to have regardless. Basically its a 60-90 second pitch about yourself. Use this to help: http://www.alumni.hbs.edu/careers/pitch/
Prepare a list of questions you may want to ask people. One I always go with is "so how did you end up here at ______?" People like to talk about themselves and it gives a long opportunity for you to identify what other branching topics you can explore during that conversation.
Bring business cards. Lots of 'em. Get theirs. If there was something in particular you connected with, write them an email afterwards to thank them for meeting with you.
I know you said you're pretty current on news... but make sure you are current, period. Before going, read a few day's worth of news about the industry. Then you'll have some fresh material to turn to if necessary during a conversation. Better yet, add your own twist on events.
Look up some of the attendees, see if there's anyone or any company you are particularly interested in meeting. Then look them up on Linkedin / Wikipedia / Google News / etc.
That's all I have for now. Hope its somewhat helpful.
Edited by byau - 9/4/12 at 4:08pm