Those people still in line won't get the coveted natural Greenbuild tote bags. Those ran out yesterday after the first 9,000 attendees.

People registering on-site (rather than registering online before the conference) won't get into the lunch plenary today. Coffee breaks and snacks are consumed as soon as they're set out by McCormick's catering staff. (Did you get a cookie?) There are long lines for bad cafeteria food, lines at the restrooms (even the Men's), and lines for the public internet workstations.

Media attention is very high. I had to schedule an interview at the Philips booth around a shoot there by Discovery Channel. Cameras, lights and grips swarmed around communications director Susan Bloom through a tour of the Philips booth. Press photographers are everywhere here, and the press room is buzzing with activity. This kind of mainstream media attention was not visible at last year's Greenbuild. (I did get the Philips interview, and Susan was as gracious to me as she had been to Discovery Channel.)

There are over 850 exhibitors showcasing their products and services at Greenbuild. This photo shows less than half of the expo hall. (EP photo)

Education sessions remain almost impossible to get into without queueing up. I observed a new trick, proving how readily people adapt: Toward the end of each session, attrition empties some seats, and those standing don't bother taking them. That creates an opportunity to slip into the room at the end of the previous session and get a decent seat. It also means waiting 30 minutes for your session to begin.

I managed to slip into a front-and-center seat at the session titled "A Business Case for Sustainably Designed Commercial Office Buildings" with John Gattuso of Liberty Property Trust and three of his architects. It was looking like a self-promo session for the architects until the last 15 minutes, when John presented some hard numbers on the three buildings discussed.

One session I had no trouble getting into was "Sustainable Communities: The Role of Utilities in Advancing Smart and Green Neighborhoods." I dropped into the session to see some speakers from my part of the country, including long-time aquaintances Mike Weedall of Bonneville Power, and PS Reilly. The small room looked about a third full, so there was at least some interest in hearing what utilities have to say.

Now, I have to go get in the cab line.

Yes, I'm taking Chicago's public transit while I'm at Greenbuild. The cab will take me and my luggage several blocks to the nearest CTA subway station, and from there it's two trains to O'Hare (about an hour). My TerraPass-offset flight gets me home by 9 tonight. There, at least, I don't have to wait in line for the bathroom.

More on Greenbuild 2007.