There are some data sources that you can use when trying to get information about Dreamwidth and its users, especially programmatically. If you're going to use a bot, please make sure and read the draft Bot Policy.
Atom and RSS Feeds
Feeds are located at:
Interest data can give you information on the specific interests a user has, or how many users have listed an interest.
You can get information on an account's icons through an Atom feed.
FOAF files are available here:
Note that users can set their own FOAF files, or limit who they list.
This is our JSON formatted replacement for LJ's fdata.bml.
It's available for all account types.
Stats on service activity are available here:
Raw stats are currently unavailable.