If you are referring to the Trading Expo in Anahiem then I would say there is value in visiting some of the vendors (assuming you don't have to spend a lot of money flying there). I like seeing what the current stuff is that the quote providors have and what new deals some of the brokers are offering. For example, I learned more about qcharts by listening to Gibbons Burke for 30 minutes then I'd probably ever figure out on my own. I also saw IB there offering 1 cent/share before anyone had heard of them.
One day should be more than enough time to see everything. I've never attended any of the seminar stuff so I can't comment on that. As they say.. those who can trade: do, those who can't: teach.
Fletch