On February 12, 2010, we published the DxOMark ranking and test results for a Canon EOS 550D pre-production model. However, as we always want to make sure that our data reflects the performance of cameras that are actually released on the market and available to consumers, we have since measured a commercial model and can now publish its results.
The rankings and results for both the preproduction and the commercial models are very similar, thus they both have the same DxOMark Sensor score. All the differences among the three component rankings for the two units are actually within the measurement confidence interval: for instance, the largest numerical difference, 23 points between the scores of 807 and 784 points for Low-Light ISO, corresponds to about 1/24 of a stop.
Only the commercial model measurements will be available on dxomark.com.