500D / D5000 noise comparison...

to me the following page shows a more definitive noise comparison of the subject cameras. Why, you ask? Because the exposure settings and NR settings are spelled out and equalized. From the two ISO6400 shots found at the following page, It clearly looks to my untrained eyes that the Canon is the better result.

http://www.digitalreview.ca/content/Nikon-D5000-D90-Compared-to-Canon-Rebel-T1i-500D.shtml

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http://www.flickr.com/photos/39169343@N04/