Two of the people I've got on my friends list I haven't talked to since they added me (I just added them back out of courtesy mostly) so in their cases I'd more or less just treat them like total strangers because honestly, they are.
The other two would get invited in, as I've talked with them both extensively on MSN and although we've never met face to face I would consider them both friends.
The other two would get invited in, as I've talked with them both extensively on MSN and although we've never met face to face I would consider them both friends.