In "The Photoshop CS Book for Digital Photographers," for the "Image Size" dialog box, Scott Kelby recommended changing the resample image interpolation method from the default "Bicubic" to "Bicubic Smoother."
In the new "The Photoshop CS2 Book for Digital Photographers," for the "Image Size" dialog box, the author now recommends "Bicubic Sharper."
I haven't tried it both ways to see how much difference it makes, but Kelby is usually right, so I'm using Bicubic Sharper with CS2.
