Our team has since switch to git. For more information read my article on our git workflow
From what I’ve been able to tell, there is no real version control built into Salesforce.com and this is a problem when pushing from a sandbox instance into a production instance. To fix this problem (at least until Salesforce does something), I think the best option is to use the Force.com plugin and the Subclipse plugin for Eclipse. With both of these in place, it should make version control a reality.