DPReview just posted a very good comparison of three of the leading cross-platform RAW converters: Capture One Pro 7, DxO Optics Pro 8 and Adobe Lightroom 4. Since the comparison compares products that work on both Mac and Windows, other options like Apple's Aperture are not included.
Link to review: Raw Converter Showdown: Capture One Pro 7, DxO Optics Pro 8 and Lightroom 4: Digital Photography Review
Link to review: Raw Converter Showdown: Capture One Pro 7, DxO Optics Pro 8 and Lightroom 4: Digital Photography Review