I've heard to the contrary - in fact, I've heard that ISO 100 medium format (not sure which one) is equivalent to around 50,000 megapixels. Digital has a long way to go.
Your comparing apples to oranges.
It depends on what your final output is, but realistically you can probably scan a medium format transparency to a 1GB file if you had access to one of the best drum scanners that money can buy AND a skilled operator to use it.
You can get a 400mb file from the best medium format backs and easily interpolate to a 1gb file, but almost no one uses that.
Analog films big limitation is it's ability to capture a wide tonal scale (i.e. dark to light). Properly exposed transparency film in a modest contrast situation might be able to capture about 1 f-stop worth of information, over or under the proper exposure, giving film a latitude of about 2-3 stops. The better digital cameras can do about 6 and the best stuff (the medium format backs) can capture 10 stops worth of range, that you can extend in photoshop.
The other area that film really falls down is sensitivity to low light. Ever try shooting ISO 1600 film? The grain is golf ball sized. I use my Canon EOS5D at 1600 -3200 regularly with no problems and still get some contrast to boot. When you push process film in low light, all you are really doing is developing the highlights more and the contrast goes way up.
The new Nikon D700 that I'm writing up right now, will produce better, cleaner images at ISO 6400 than the Olympus E-30 we reviewed last issue could at ISO 400.
The last area that film really falls short with (and it's more a fault of a film based system) is edge to edge sharpness of the frame. Because film has an inherent curve, it's really tough to maintain image sharpness at the corner of the frame with the slight curve to film. The digital sensor, being perfectly flat eliminates almost all of this problem.
There's plenty of other great reasons why digital is a lot more useful than film. And I probably wrote about 500 articles over the last 12 years, but my biggest complaint with film was getting rid of dust. When I used to shoot film and have high quality scans done for advertising clients, I used to spend between 1-3 hours just cleaning all the little dust specks and other crap in the scan.
And let's not even talk about the other fun parts of the process, like the lab destroying your film in the process, a moron running the scanner, etc etc.
I wouldn't go back to film for all the tea in China. Sure, I miss my old 8x10 Sinar some days and looking at those big transparencies on a light box, but it was a lot more work. Not to mention reshoots when the art director changed their minds....
