The main difference is that the A85 has manual controls and the CX7530 does not:
Manual Focus
Aperture Priority
Shutter Priority
Program Mode
Manual Mode

The CX7530 is 5 megapixel and the A85 has 4 megapixel.
The CX7530 photo shows more detail than the A85.

The CX7530 has less shutter lag than the A85.

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Note: The Canon A85 has been replaced with the new Canon A520.

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