This thought was brought up in a roundtable discussion at Mailtrust, a company which uses and develops open source software. I found the topic incredibly interesting because we all denied computers as being appliances, because generally we knew how they worked and how to use them. However, we knew it was true since that's how the people who don't know how to use them think about them.
An appliance has a very specific use. Some general appliances one may see in a person's house or dorm are refridgerators, washing machines, toasters, microwaves, blenders, air conditioners, televisions, and other such things. Although, one important feature seems to be left out of the definitions. A trait of these objects is all knowledge about how they work is ambiguated away. This important feature is what separates an appliance from a tool. It means that the least amount of effort will generate the greatest amount of results.
The toaster has a button one pushes to start toasting, then they walk away. A refridgerator keeps ones food cold, or frozen, but how does this actually happen? Can one actually get cancer from standing too close to a microwave? Probably not, or else it would not pass FCC standards, not to mention a slew of other standards. That's why there's a little screen in the little window, and why the microwave is so thick. Yes, one might get cancer holding a constantly activated microwave to their body for a very long period of time; otherwise one is more likely to get cancer from the sun with the same kind of exposure.
So we, the people, have a bunch of appliances which do things, and we have no idea how they work. Do computers fit into this category? I would say, 110%, yes. How many people do you know who don't know anything about computers? Some of them may be interested in how it works, or at least an overview of what happens. However, some simply don't care how their computer works. What matters to them is IF it works. If the computer is not doing what they want it to (I love this paradox because really the computer is doing exactly what it was told to do, blue screen of death aside), then there is a problem with the computer. God forbid there's a problem with the user. These are the people who see computers as appliances.
A good analogy to what is happening to computers is what happened to the car. Cars have been seen as appliances for a long time, but they were much more widely accepted as tools. To the normal user of a car, it gets them from point A to point B. There is a very simple and intuitive interface, and definitely the least amount of effort will generate the greatest results. However, there are people who don't see cars as appliances, but rather as tools. One finds they can modify the car, get better gas milage and fix it at a cost much less than the dealer will offer. They put more effort into their car, and therefore can squeeze even greater results out of it. The same can be said about computers.
Is it a bad thing that it is even possible to view computers as appliances? There is a quest among most software developers to make their software as accessable as possible to the greatest audience. Some software does not make it past a small niche, and stays useful that way. Some software hits it big and spreads around. The less effort one has to put forth to generate results, the more people will be willing to use it. Sometimes it is the case that the only reason software does not spread around is because people are afraid to try new things. They don't know how it works, or are afraid of 'messing it up'. This kind of person usually cannot or does not want to learn about how to correctly use it, and never progresses unless someone teaches them.
In the end, it is never good to have something which is seen as an appliance. It becomes the breeding ground for ignorance and complacence. The computer may follow in the footsteps of the car, although that may not be too bad. Most people know how to add oil to their car or diagnose problems with rudimentary knowledge. Hopefully computers will come to a point where this kind of knowledge is widespread. For cars, it took almost 100 years to get to the point where we are now, and maybe once the age of the internet approaches 100 years, that same sort of universal understanding will be widespread.