(via Lessig blog and various mailing lists) Licence geeks know that Wikipedia is licensed under the GNU Free Documentation Licence (GFDL). This is a nifty little licence used for publishing documentation with software projects. However, the GFDL is incompatible with Creative Commons licences. The incompatibility comes because the copyleft clause in the GFDL only allows for redistribution under the unmodified terms of the same licence. It also allows for commercial reuse of the work, which makes it incompatible with the more popular CC licences (BY-NC-SA and BY-NC-ND). The closest licence to the GFDL is Attribution/Share-alike.
Now the Wikimedia Foundation has announced that it will allow migration to Creative Commons BY-SA, which is a huge step in the standardization of CC licences as the option of choice for open content (as an aside, SCRIPTed is moving towards Creative Commons as default licensing option). This a momentous change for Wikipedia, and certainly a welcome one. There are several questions as to legitimacy, and whether or not contributors should get a say as to the licensing of each article.