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Palm being a serious company, you can be sure that they took this step in a calculated and serious way.
On the face of it, Eugenia is right, you should not use another vendor's id. But they know that, of course. They are deliberately making a point. The point is something like this.
We all subscribe to a standard, they are saying. The objective of this standard is open connectivity. Now, one of us is using his unique ID to prevent this, to lock his device to his software in some important aspects of functionality.
Fine, we are saying. If that's how you want to play the game, we will use your unique ID. If you don't like it, why don't you sue us? Lets get this thing out in the open, and lets see whether the USB consortium thinks this is what unique IDs were intended for. And lets see whether the public, when it has it explained to it what is going on, thinks this. And lets have you explain why this is so much better for the iTunes users than being able to connect as they choose to whatever they choose with full functionality.
Apple does not realize that it is, with this and other similar stuff, playing a very dangerous game. It is being egged on by its cheerleaders, who also do not realize how dangerous this is. The danger is not so much that the legal position will not be validated by a court. The danger is that they will win in court of law but lose in court of public opinion. Once public opinion shifts, Apple will no longer be cool to the general public. That is what they have to lose, and they are getting closer to losing it with every one of these episodes.