I've been seeing (and hearing) a lot of misinformation about the SharePoint 2010 Content Editor Web Part (CEWP) from people that assume it behaves exactly the same as it did in SharePoint 2007. This is also then used as a rationale as to why you should use page fields as part of page layouts (i.e. the "Page Content" field) to store content - "if you want versioning, you have to use page fields and page layouts. Period! CEWPs just don't support versioning". This is incorrect!
On the contrary, the SharePoint 2010 CEWP does support versioning and you can easily roll back to a previous version of a page with the content of all your Content Editor Web Parts still intact from that old version. It would appear that this is one of the less-well publicised "new" features of SP 2010.
Some entries on the blogosphere which indicate (erroneously) that content isn't versioned within CEWP in SharePoint 2010: