How to Connect at a Convention
Microsoft works hard to help people connect. From the moment you register, you can set up a personal profile in the Convergence Connect  web site. The web site also allows you to set up meetings at the conference in an area set aside for that purpose. For example, someone invited all CFO 's using Dynamics NAV to a meeting. Even though we were in industries ranging from a zinc parts manufacturer to a church, we found we had a lot in common and decided to meet again after the conference.
Microsoft also plans for chance encounters. Here is a picture of my conference badge. You can tell which software I use (Microsoft Dynamics NAV ), which industry I'm in (Non-Profit) and which user group I belong to (NAVUG ) because there were bins where I could pick up the buttons. On the last day of the conference, someone with another faith based organization saw my Non-Profit button and said she had been looking all over for someone to talk to about the software choice they were about to make. We talked for about half an hour about NAV and also agreed to contact each other after the convention.
Other features: on the back of the badge is a pouch with a miniature schedule, which helps you know where to be when. People also used it to store their business cards. It wouldn't be Microsoft if it weren't computerized. The plastic name badge contained a chip with my information in it. All a trade show vendor or the people at the doors of the sessions had to do was point a reader at the card to record my information. I didn't even have to remove the card from the pouch.
Getting conference feedback is difficult. Microsoft computerized the session evaluations, made them short, offered a $5,000 travel voucher as a prize and said they would donate money to a the local Boys and Girls club for every evaluation completed. Still the number of evals completed was a fraction of the total number of sessions attended.
Finally, with that many people, it can be hard to make them all feel welcome. At Convergence, they had information booths as well as a small army of people in red shirts available to answer questions or tell you how to find the room you're searching for.