What are licensing & copyright considerations for songs & spoofs on YouTube?

What you're referring to is the "fair use" defense in copyright law. Below is short, relevant summary as to your question. Note the distinction between parody and satire.

Question: Is my parody of another's copyrighted work protected as a fair use?

Answer: It is likely that a bona fide parody, as opposed to satire, that does not usurp the market for plaintiff's work or unfairly free ride on plaintiff's work will be protected as a fair use. See Campbell v. Acuff-Rose Music, 510 US 569 (1994). Courts have held that the fair use defense can protect a parody of a copyrighted work from an infringement claim. However, that does not necessarily mean that all parodies will be protected. In the case of a parody where the defendant raises a fair use defense, the courts will run through the four part fair use analysis just as they would with any other fair use test. [See above for the four part test].

While it is problematic to try to predict what a court will decide in any fair use case, it is likely that in the case of a parody the court will focus on the fourth factor of the inquiry, which requires the court to ask what effect the parody has on the potential market for the copyrighted work. If the parody usurps the market for the copyrighted work, then there is an increased chance that the court will find that the use is not fair. If the parody dampens the market for the copyrighted work as a result of its implicit criticism of the work, such a negative effect on the market does not render such use unfair.

http://www.chillingeffects.org/fairuse/faq.cgi#QID...

Generally speaking, you are better off with a license because that avoids the need to rely on a fair use defense. As a practical matter, it's impossible to know for certain whether your fair use defense will prevail until you are before a court.

Two matters: one million) The video is on-call for, and can obviously develop to enormous quantities of perspectives two) The video CAN be downloaded - it is being downloaded as it's regarded, and will also be downloaded utilizing equipment. A brief component of a copyrighted tune can be utilized if: - You use a small, unsubstantial quantity of it - For functions of comparable parody, schooling or feedback