No more rumors, it's official: Microsoft announced a CMIS connector for SharePoint 2010!!! More details about the announcement can be found here on the Microsoft SharePoint Team Blog.
SharePoint 2010 will contain a CMIS Consumer Webpart to display Contents from other Content Management Interoperabillity Services repositories. Maybe a big step to Composite Content Applications!
If you are more intrested in CMIS, check out this links: