[The system is logging you out right now.Your Account will not be available until ...]

I get the same thing also very often and one reason is when many prims are attached to you but also one tip is when you see the message to try and log in again, to wait for the picture in login window to load, then log in again. They have a failsafe on login time to prevent spam I think and it also lock you out  for longer if a new request is sent to early

[IP Address Privacy?]

You really should think about the fact that shoutcast servers (most SL media streams) list listener IP, but that is not Second Life related at all.

You are worse off with your facebook and twitter accounts, and a google search with your name comes up with 4000 hits.

Most blogs will record your IP, so will most (if not all) forums so think about that when posting something somewhere.

So if you want to be anonymous, pull the plug to Internet.

Best way is to ask yourself what someone could do with your IP, and more important: why they would bother.