That only provides one extra stop of dynamic range according to
dpreview.com, <IRONY> a noted authority.</IRONY>

Despite aforementioned noted authority saying DSLRs have 8 stops range,
most real photographers feel they have about the same as slide film,
5 stops.  Negative film has about 10 stops, sometimes more.

Exactly.

With raw capture, the 5D at ISO 400 holds detail in zones I and IX, which is
two more zones than you need for the zone system, in which zone I is true
black and zone IX pure white. (More accurately, it's enough to support up to
the equivalent of N-2 developing.)

Here's the proof.
http://www.pbase.com/davidjl/image/76131098/original
http://www.pbase.com/davidjl/image/76131302/original

But color negative film can be overexposed 3 or 4 (or more!) stops and still
produce a decent print. C41 is seriously amazing.

Of course, there's no such thing as a print that really shows all nine zones
of the zone system (outside the very best of the B&W art prints, but we're
not in that world). So the question then arises as to whether it is
significant that color negative film can capture serious detail in zones X,
XI, and XII. When you make a print, the high end all gets mushed into one or
two zones. So if you've got a seven zone print (even this is serious
dreaming, but lets pretend), a correctly exposed 5D image compressed so that
the top end lives in zones VI and VII (here zone II is black and zone VIII
is pure white), you've got something like 4 or 5 stops of detail from the
subject compressed into zones VI and VII and everything above that in zone
VIII. Is that going to be all that different from a color negative print in
which seven stops of detail from the subject are compressed into zones VI
and VII?

I doubt it. (Actually, you'd probably prefer the 5D print, since the detail
would be useful. With the 5D, I find I need fairly heavy-handed sharpening
to bring out detail in the brighter zones. (Grumble: Lightroom has a trick
for masking edges, but it does the opposite of what I want. I hate halos,
but I like textures, so I want to hide the edges from the sharpening and
only sharpen the textures. Grumble.))

And I suspect that even the better 4/3 cameras at ISO 100 will do nearly as
well, if not just as well, as the 5D at ISO 400.

(If the zone stuff above didn't make any sense, "The Confused Photographer's
Guide to On-Camera Spotmetering" is an excellent (and basic) introduction to
zone system concepts. I also like "The Zone System for 35mm Photographers",
since it describes the nine zones of the zone system well.)

David J. Littleboy
Tokyo, Japan

I'll second that.

Being a former long time 35mm SLR enthusiast (several decades!), I finally
took the plunge into digital a few years ago, and bought a Canon Powershot.
Now having got so used to the convenience of always having a compact camera
available wherever I go, I wouldn't contemplate going back to the "good old
days" of lugging all that camera gear around again. Admittedly I'm not
getting the same absolute quality as my old SLRs, I have a couple of high
end prosumer cameras for that event, I'm finding it so liberating always
having a camera on hand, plus it's also so much more discrete than a large
SLR.