Before the launch of MSN Messenger, there were other proprietary Instant Messaging protocols going strong, like AIM and ICQ, but Microsoft used its monopolistic position to push it's own protocol and installed Windows Messenger by default on Windows, as done with Windows Media Player and Internet Explorer, following Microsoft's lock-in strategy. Being it based on a proprietary protocol it's very hard to write reliable alternative, non-official clients, usefull for example on platforms other than Windows.
Reasons to not use MSN may include:
- you don't want to be locked to Microsoft for the rest of you life. Yes, you cold always use alternative clients that support MSN. It has already happened however that Microsoft suddenly slightly changes it's protocol with the consequence that a lot of alternative clients stopped working, even outdated versions of the official program won't connect anymore
- it's a proprietary protocol, there is an alternative, called Jabber, witch is open and based of standard protocols, witch means it's a lot easier to implement and it's supported by a lot of clients
- privacy concerns, you may not like the idea of all you conversations going trough Microsoft's servers
But all my friends use MSN...
Well... that's exactly what the Microsoft lock-in strategy is all about, use it's monopoly to make enough people use it's own technologies in order make it very difficult for people to switch back to anything else. Fortunately there is a way out, using one of the multi-protocol client's, like Gaim, that allow you to use Jabber, MSN, AIM, ICQ, Yahoo! and others with the same client or alternatively using a plain Jabber client and use the gateways offered my some Jabber servers to connect to other networks.
Lately Jabber is starting to become e bit more widespread thanks to Google who used it to implement Google Talk, whoever wants a gmail account, witch automatically creates also a Google Talk account can e-mail me at nimatar(at)gmail.com to get in invite.
My Jabber ID is firstname.lastname@example.org