I believe that a major cause of the decline in magic's image is the rapid rate at which technology improves and scientific advancements are made. Most people now are very fixed in their mind set of "I know what is, and what is not possible. If it does not coincide with my knowledge of science, and what I 'know' to be true; it is a trick."
You cannot blame the decline of magic in the sence of how realistic it is portrayed and persieved purely on people's poor performances over youtube. This makes the assumption that the wide majority of an audience has browsed for, and viewed poor performances.
One way that you can tell that the increasing quality of education affects the way magic is persieved would be to perform for a younger child one on one. I've done this a couple of times for the sons / daughters of some friends of mine and have realised that they are very open to the concept of magic. They will, however, usually not hesitate to tell you when they believe that they have an explanation. The problem comes from the fact that many adults believe that they already HAVE the explanation, and that the details are merely to be found out. This is also why some tricks these days can cause spectators some pretty severe confusion when they are unable to match what happened to any logical explanation that they can come up with.
I think we're at a turning point in the art. With the media revolution, things will change. Magic will no longer be seen as realistic as it once was. Let us try to move into the next era, where magic can not only be considered an art in OUR eyes, but the spectator's aswell.
Another main difference between now and hundreds of years ago is the fact that now, magic is a common form of entertainment. Where-as it used to be a mysterious act that would have it's spectators spreading rumors about. That brings me to my next line of thought; the methods of communication now also affect the world of magic greatly. A long time ago, stories would be told, and those stories would through excessive telling become exagerated (what I like to call the "I once caught a fish" effect xP). Now with the new, sturdier methods of communication, stories are less likely to have the same amount of exageration (stuff like 'carbon copies' in emails and video recordings for example).
And finally, I get to the topic of videos

. Now that magicians are being recorded, or in many cases record themselves, potential live spectators can simply go on youtube (for example) and view magic to their hearts content. This of course leads us to the magician's worst enemy: THE DREADED REWIND. Spectators can now rewind, and rewatch the same effect over and over untill they get some idea as to the method. This can be an instant kill to any effects recorded that use misdirection as their main element (two examples from the Trilogy of this would be "Card Across" and "Hand to Mouth").
As a final note, I would just like to say that the changes do not have to be bad. Change happens, we can either adjust, or not. Personally, I will do my best to adapt magic to the 21st century, as our decendants will have to do after us.
*END WALL OF TEXT*
ehm, sorry.. It's late.. flying to the states tommorow, had nothing better to do
