Micro$oft has done the same thing they did to Netscape. Abuse of Windows’ total domination of the market.
I still think that ICQ is a superior IM client and a lot more reliable than MSNM! It has features, and has had features for several years now than MSNM doesn’t include yet! Offline messages, message history, send contacts, invisible mode (show offline sucks comp. to it!) to mention a few.

It’s a security thing. Some of the older clients were coded with security in mind so to protect your privacy, always keep the box checked.