There's no doubt that there is something inherently consumptive about 1500 people traveling to a big city and shacking up in a big hotel and being on their laptops and mobiles and Flipcams all day...not to mention eating, drinking and generally making trouble.
I hope Jes's post makes the point that big things are awesome (like the fact that Michelin is offsetting 200 tons of CO2...the approximate burden our conference creates) but that small things matter to. Like providing our 50-page conference brochure in an online-only format that we encourage people not to print if they can possibly avoid it. Or going with buffets instead of box lunches like we had last year, so to avoid all that packaging.
There's always further to go, but I'm proud of what we are improving each year to be greener and yet greener. This year we had and awesome Green Team helping us, so check them out!