In common with many experienced Mac users, I feel slightly helpless and all at sea when it comes to Autos Save and Versions which arrived with Lion. I fear that one of these days something will go wrong and I will end up with the wrong version of a file. This is all the more worrying since I store all my data on Dropbox so that it can be fully portable across my Macs. I used to feel in control of my documents, but…..
Here’s a bit more background I gleaned from a Macworld article by Chris Breen. I’m glad he understands what’s going on because I find it somewhat worrying:
As for transferring documents, no, you can’t move files to another Mac and expect their versions to travel with them. Versions are not embedded in the documents. Rather, they’re stored in a hidden directory at the root level of your hard drive called .DocumentRevisions-V100. The application then references the versions in this folder when called upon to do so. The versions of your document are missing on the Mac you’ve copied the document to, so no versions are available.
Now I’m even less sure of where I stand with my documents.