The most significant fixes in the Photoshop 10.0.1 update include the following:
The speed of moving objects contained within multiple layer sets has been improved.
Converting images to CMYK using certain profiles no longer results in black files.
The Save for Web feature now includes an option to "Include XMP" (metadata) in the settings menu within the main Save for Web interface, making the existing capability easier to access.
When using Save For Web with "Include XMP" enabled, all XMP data is now included in the optimized file.
Print color matching has been improved.
Images saved as DICOM and reopened in Photoshop CS3 are no longer corrupted on PowerPC based Mac computers.