Drew mentioned that Apple released an update to Aperture. This is probably the first of many though don’t expect anything major:

• White balance adjustment accuracy and performance
• Image export quality
• Book and print ordering reliability
• Auto-stacking performance
• Custom paper size handling

Aperture depends on the ImageIO Framework to do the file handling and Core Image to do the majority of the heavy lifting in the UI. So the largest changes should be expected when Apple updates the operating system, not Aperture.