I have changed our "How to contribute" page to note that CLAs are not required, a piece of information I learned from Todd, one of our mentors.
https://cwiki.apache.org/confluence/pages/diffpagesbyversion.action?pageId=65147115&selectedPageVersions=12&selectedPageVersions=11 Note that CLAs are required for Impala Committers, but if you are one, we already have one from you: http://incubator.apache.org/projects/impala.html
