That's an interesting question -
I still think quality is degraded somewhat when scaling an image, and images are always at best quality at 100% of original size (both scaling up and scaling down causes somewhat quality loss, although there is less loss with scaling down)
We use a setting in the Imagevue slideshow _quality = "best"
Which somewhat improves the image smoothing and anti-aliasing when it's being scaled. The default setting is "high". Below see how the Flash documents describe the settings:
Adobe wrote:"HIGH" High rendering quality. Graphics are anti-aliased using a 4 x 4 pixel grid, and bitmaps are smoothed if the movie is static. This is the default rendering quality setting used by Flash.
"BEST" Very high rendering quality. Graphics are anti-aliased using a 4 x 4 pixel grid and bitmaps are always smoothed.