Safest of 2006

The IIHS has recently released its list of the safest 2006 cars. The list and an explanation of the criteria can be found here. Some have noted that vehicles from manufacturers such as Toyota, Volvo, Mercedes-Benz etc. are not represented. Judging from this paragraph

"A number of automakers requested early tests, and based on our discussions with the automakers we believe no other 2006 models would meet our Top Safety Pick criteria," O'Neill says. A number of major automakers including BMW, Mercedes, Nissan, Toyota, and Volvo aren't represented in the first set of winners.

it seems that no other models would have won if they had been tested. Thus, the ones shown are the best of the model year.