My dishwasher has several cycles: Rinse, Quick Clean Up, Light/China, Normal, and Baked On Cookware. They differ in the length of time the machine runs. Quick Clean Up lasts 45 minutes, and it's supposed to be for washing the pots and dishes you dirty up while preparing the meal. Normal cycle lasts more than an hour, and I've never used the Baked on Cookware cycle.

I was curious as to whether besides taking longer to run, the different cycles used more or less water. Apparently not. According to what I found on the Internet (and you know how accurate that is) my model of dishwasher uses 4 gallons of water each time it runs regardless of which cycle, except the rinse only cycle is uses 2 gallons. The article I was looking at said that if you wash or rinse dishes by hand, for every minute the water is running, 2 gallons of water is used, so hand washing quickly uses more water than running the dishwasher.

You can find out how much your own dishwasher uses by following the Energy Star link from this site:

The Practical Environmentalist

Of course there are some things to keep in mind:
-- Scrape the dishes off, but don't pre-rinse them before loading into the dishwasher. Of course there's times you need to pre-rinse, but figure out how dirty the dishes can be for your dishwasher in order for them to come out clean

-- Only run the dishwasher when it's full

-- To save energy, use the economy dry selection, or open the door and let the dishes air dry

I have used cheap dishwashers and top of the line dishwashers, and the main differences seem to be how quiet they are, and how fancy the racks are.

On really cheap ones the rows of tines that hold your plates on the bottom rack are all equidistant. This is less than ideal because where the spacing varies, you'll find there is a perfect spot for your Corning Ware casserole dish or that favorite mixing bowl. High end features also include little sub-racks that flip up and down to accommodate different shaped dishes and pans, and sometimes the top rack can be raised and lowered to make room for very large pots.

Other features on the high end models include little doors that cover one of the silverware compartments so you can put tiny lids and things in there safely, and clips or holders for your wine goblets. My fancy dishwasher has those, plus a little mesh bag attached to the upper rack for other small things that might fly around inside there, but I don't use it very often. Maybe it's to put the kitchen sponge in.

My non-fancy dishwasher is okay, but I find I miss the variable spacing on the racks. Also, it's a Maytag and they have recalled 1.7 million of their dishwashers because of a fire hazard, so we have to have the repairman come and make some repair.

If you don't want to bother with the repairman, you can get a rebate towards a new dishwasher, but it won't cover the whole cost. This would make sense if you have an older dishwasher, but ours is only a couple years old. I have to admit I seriously contemplated taking the rebate so I could get a fancier Maytag, but realistically I don't use it enough to warrant the extra expense.

More Information:
Maytag Dishwasher Recall 2010