Adobe Labs has released a Release Candidate update for Lightroom 4.1. A Release Candidate is a pre-release of the update to get user feedback and make sure it works good before the official release. New in the update is support for the new Canon 5D Mark III and some bug fixes. If you're a 5D Mark III user I'm sure you will want to try this update right away so you can use your photos with Lightroom 4. You can download the update and read more about the changes here.