The tests looked at how many hydrocarbons and carbon dioxide were emitted. The worst scooter tested (from 1968) spewed out 4,900 parts per million of hydrocarbons and 8.6 percent CO2 emissions. A more modern scooter (2006 model) had 168 ppm of hydrocarbons and 3.1 percent CO2. The SUV? 10 ppm and 1 percent CO2.
The problem, of course, is that the tests didn't factor in any sort of mileage that the tested vehicles can travel while they emit these pollutants nor do they measure the emissions using the grams per mile standard. Readers pointed these errors out in the comments, but the article has gotten a lot of play in online scooter communities.
[Source: Willamette Week, Hat Tip to Chris Nelson]