> Probably true. Do you have examples of what you're thinking of?
Bookmarks, contacts, notes for example, they are usually not time-based but by context, category or whichever organization their usage demands at the moment. They can be time-based in a journal, but usually I do not remember websites or people by the time I encountered them, so I would not search them this way.
The other question is how personal is personal in this project? Are my IMDB-ratings valid data for this? My Ebook-collection? My Steam-account? Those are usually things I would not manage in a timeline or a map, but with different interfaces and features.