Flickr Hive Mind stores no personal information no photos, not even a thumbnail. Some general information ends up in my apache server logs (time, IP address, link), these logs are removed every 2 years.
Flickr Hive Mind uses a cookie, only for people who have logged into flickr, to remember who you are when you return and to show you your personal photos. This information is not shared with anyone and I do not use it for any other purpose.
Flickr Hive Mind uses google analytics, which collects anonymized activity data on my site for a period of 14 months.