I’ve only dealt with issues of data loss a few times – but it’s generally very difficult to know much for certain.
You find out about the issue after-the-fact – sometimes a long while after – and by then all logs and data and recollection of the event that triggered the bug have faded.
I think, for now, all we can say is this is our best guess. Under that assumption a good way forward would be to:
- enable time machine and ensure it’s working saving backups regularly
- replace missing images – and other data types that may be susceptible:
- blog posts
- photo album photos
- Collage photos
- be more vigilant than usual – on the lookout for similar problems
If you do run into new problems there are probably a few things that can help all the developers looking into this:
- the before/after files – seeing both the backed up OK file and a file post corruption can give a clue as to how the corruption occurred
- the console logs – if you notice a problem right away open the console and copy your logs
- crash reports – these sorts of things don’t always cause crashes, but sometimes they do. if that happens, save the crash report – or send it using the built in crash report – include info about what you were doing when the crash occurred – be as detailed as possible.
I’d also like to give a 
to the devs working on this. Not easy stuff. If there’s anything I can do to help you guys out let me know.
Isaiah