I use M and Av. In my opinion auto and manual are states of mind. If the photographer is in M, and just zeroing out the meter every time that's no different than running the camera on auto. The control comes from interpreting what the meter is telling me. All of my digital cameras display aperture and shutter even in the auto modes, so I can see what the camera is doing. If I want to adjust the exposure in auto I can use exposure comp or point the camera at a particular tone and use the meter lock. But it's just as easy to leave it on M. It's only 2 controls: intensity and time. Those are the same controls we use to make perfect toast and fill glasses of drinking water without spilling. People get it in their heads that exposure is tricky, but they regularly perform much more complicated tasks in their everyday life without thinking about it.
I use Priority and aperture and shutter alot but mostly P the only time I will use auto is if I am clicking white flowers as it brings them up to the true color for scenery I use P and spot metering and ISO 200 and adjust my exposure to suit
It really depends on the subject. If I am shooting landscapes I generally use manual so I can adjust for different light effects. When shooting a get together with a lot of people, I use P mode because the camera is pretty smart with the automatic settings, and I can concentrate on framing my shots, not on camera settings. I have an Olympus E3, one of the finest cameras I have every owned and I have owned quite a few over the years. It is a DLSR with live view that shows me a histogram as I am framing the photo. I usually shoot in RAW and do minor adjustment in Photoshop CS3 or Lightroom. If I am doing special DOF, I will use A to get some focus control. When shooting action shots, S is a good way to go. It all depends upon the situation. Isn't it great to have some many options. I do not miss my old Canon AE1 film camera at all.
I use a Canon 1Ds & a 40D and shoot M - 90% & Av - 10%.
M - Manual, Av - Aperture Priority, Tv - Shutter Priority, P - Program Mode (like Auto)
Carlton
90% of the time it's on M. I use the histogram to confirm exposure, the screen, I may glance at to check composition and in group shots to confirm eyes and expressions, or do I need another shot. My first slr was a Miranda, no meter, my base line was the info on the Kodak film box and my best guess. That usually worked. I shot mostly b&w asa 125 or 400. So you learned to read the light. But then everyone is different. I've tried p, a, and s. I'm rarely happy with their best guess. They could leave those choices off my next body if it would save me a thousand or so.
"They could leave those choices off my next body if it would save me a thousand or so."
Leaving those features off a camera would cost you thousands more. Small format SLRs are designed to be do it all cameras so that one camera suits the needs of as many photographers as possible. DSLR prices are based on being able to sell tens and hundreds of thousands of units. A stripped down DSLR would be of interest only to a handful of photo enthusiasts. Sales would be counted in the thousands of units at best.
Look at the Leica M8. Any entry level Nikon or Canon outperforms it on numerous levels, and it costs 10 times what they cost. Some of this has to do with the value of the brand name for the cultists, err... Leica-philes, but it's got a lot to do with low production and sales numbers.
I am in a constant state a flux. My lens system dictates what mode I may be using at the time. I have a tamron system w/ the adaptall mounts for Canon, Pentax, Nikon, and Leica. Also, the subject matter has some envolvment in this decision.
My macro work is from a 90mm macro, (manual) 180mm macro (auto) lensbaby (Manual)
People (auto) journalism (auto)
Weddings (auto) commercial (manual)
Portraits (manual) Night time (manual)
If the subject dictates it Shutter or aperture priority. It truely depends on the subject matter.
The above is for a Nikon D90 and does not relate to other systems that I may use as the metering systems work w/ the various lens system that I employ.
I usually shoot in program mode. But recently I shot a motorcycle track day for the motorcycle enthusiast web site I belong to using in Shutter priority mode for the first time.
I think people are confused. Av, Tv, and P were not created for use by beginners to make photography easier any more than automated nail guns are used by weekend fixer-uppers or auto-pilot is used by non-pilots. They are tools that pros wanted because electronic switches are often faster than manual switches. They work in a highly predictable manner, and as long as the photographer understands exposure and metering there is rarely a problem.