Good morning everyone! I just found some screenshots made by Alexjamesrook (reddit), of a new feature: Player notes. They work like small descriptions/a kind of WoT post-it (for remembering stuff later) to me.
You can only do this from the contact list so they have to be a friend, clan member, or black listed (or recruit but those should be on your friends list):
As far as I can tell, you’re the only person who can see the note. Just hover over their name in the contacts list and the note appears at the bottom. There’s also a small icon for people you’ve made notes for.