>- People won't keep their availabilities up to date. They won't like you asking them to keep their availabilities up to date either. They really won't like you

>- People won't keep their availabilities up to date. They won't like you asking them to keep their availabilities up to date either. They really won't like you asking them where they're working this week. StackOverflow Careers handles this rather nicely. If you mark yourself as available and are contacted, you get a notification email. If after N days you don't respond (through SO) to the contact, you are automatically marked as unavailable. It's not perfect, but in most cases it should remove stale list entries after their first contact.