Wikipedia is taking votes to decide on relicensing its content. In fact this applies to all Wikimedia Foundation sites, which have been currently licensed under GFDL, which was primarily intended for software documentation. If approved the content will be dual-licensed under CC-BY-SA along with GFDL. This required a change in the GFDL to permit relicensing for wiki sites. The benefits? Wikimedia sites will have better interoperability with sites under CC-BY-SA license, which is quite popular, and sider reuse of content from Wikimedia sites. I am sure this will work as a boost for the Creative Commons licenses as well.