You could scan your film at 120'000 x 80'000, but you wouldn't gain any more useful information (you'd just end up with a nice images of dye clusters and silver nitrate crystals)
Whereas an 8-12 megapixel image file from a DSLR has 8-12 megapixels of actual information.

In practical/printing terms (assuming normal viewing distances and not doing some fetishy like examining slides with a loupe), 35mm film maxes out at between 6&8 megapixels.

When I go to Alaska in a couple of years time (kayaking), I will take a manual camera loaded with slide film (not Velvia; too saturated) as a backup, but my DSLR will be taking most of the images.
( custard, Sat 23 May 2009, 21:59, archived)