If we don't make a system where that data can be bought and sold based on the preferences of the person being data mined, then privacy will be blown out the window in just 30 years. There will be no reason to introduce yourself to people, all they have to do is access your logs.
All it takes is one person who knows what they're doing to find out a -LOT- about you.
There are some secrets that everyone, even in a family, keeps. People can't know if you don't tell them, but with the advent of the computerized era, information escapes even if you don't tell it.
The one I am concerned is not my friend sharing a photo, is the data corporations and governments capture about me (with or without me knowing about). It was said here also, if you can make an infringement of the law, never know about it, and be held guilty by data you didn't even know to exist (the example being the import of foreign cheese in the US, even for personal use).
Then, when I want to query the data, a client-side Javascript app can display it on a timeline on a map. You plug your encryption key into this client-side app.
It would also be cool to create a host-proof method for indexing the location itself, so I could ask the service for all of the logs within a certain radius of a location. Not sure how to do this securely yet, though.