wonder-PONDer: copyright issues

I think there are a number of misconceptions about copyright. I am a law/media studies student, so I've studied it from a slightly different angle to what we're taught in the creative industries faculty. These are some myths I've noticed so far:

1. Copyright prevents ideas from being in the public domain.
Not true. Copyright does not protect ideas, you cannot get copyright in an idea. Copyright protects the specific expression of an idea, ie a 'work'. The 'Da Vinci Code' case is a good example of this: Dan Brown used the themes, ideas, even some characters, from the book 'The Holy Blood and the Holy Grail', yet did not infringe copyright.

2. Copyright is the same as plagiarism.
Also not true. Plagiarism is an ethical concept, not a legal one. You can actually be found 'guilty' of plagiarism by the university without having breached copyright. Therefore, it's a good idea to know the university's specific rules regarding plagiarism, as they are not all as commonsensical and logical as you would expect.

3. Copyright is bad.
Copyright works to balance the competing policy demands of protecting the author of a work and promoting continued human progress. All progress is based on building on the works of the people who went before us (imagine if every scientist had to first discover the wave-particle duality of light for themselves, we'd definitely have no map for the human genome), yet if we don't give people offer people protection for the work that they do do, then there's no incentive to go out there and discover/create new things, as someone else can just steal it right off you. I think copyright in its current incarnation does a good job of balancing these two factors.

4. Copyright should last forever.
Well, this isn't so much a myth as just a proposition that I disagree with. Some people think that works should never enter the public domain, ever. If this had been the case in the past (obviously the law couldn't apply retrospectively or all (academic) hell would break loose) then we would not be able to perform Shakespeare's plays, cite Aristotle's speeches or write out Gallileo's theories. Copyright should have a finite life, or wonderful wonderful works of art and culture will remain inaccessible.

5. Creative commons is the coolest thing ever.
OK, so also not a 'myth' as such, more a gripe: I really hate how in some creative industries subjects we are forced to publish/submit out work under a creative commons copyright license (KCB335 New Media Technologies!!!!!). Isn't the idea of creative commons to give creators more choices? So why force us to use them? Give us a choice. Rant over!