It isn't new. Anything you've ever written on AOL IM, or ICQ, MSN chat, or any of the other free IM services belongs to the owner of the service. They own it, and can use it as they see fit.
You really, really, really want them to give you a copy of your chat three months ago with the friend who subsequently was killed in a car wreck? "sorry, we don't have that available".
You're under investigation for allegedly violating terms of service in a chat with someone else three months ago? surprise, surprise, they've got every keystroke.
You're under criminal investigation, lo and behold, there are notarized copies of your chats going back for years produced as "exhibits 1 through 12,537"
As I've told people for years, don't consider IM to be a confidential medium, and never ever ever put company, personal, client, or any other sensitive information into a chat unless you are the owner of the chat server or your relationship with the chat server owner is one such that you'd be comfortable handing them notarized transcripts of every chat for their retention and possible use.
Edited to add: don't be paranoid. You're not doing anything wrong, so what's the problem?