End of the line for MSN Web Messenger
Since earlier this year a newer replacement service for MSN Web Messenger has been available as part of Windows Live Hotmail, featuring direct integration with the email interface and your contact list (known as Windows Live People). This will now become the only officially supported web-based client for accessing the Windows Live Messenger network, apart from the Windows Live Messenger Web Toolkit which allows developers to integrate messaging controls into their own websites.
The new web messenger service is available directly from your Hotmail inbox and acts as another location for Messenger's multiple points of presence (MPOP) feature, meaning that you can sign into the web service whilst still signed into the Windows Live Messenger client on one or more computers. Once signed in, it allows you to easily see which of your contacts are online and if the sender of an email is in your contact list then you can even see if they are available to chat when reading their message. If your Live ID doesn't use Hotmail for its email (as it is hosted on another domain) then you can still access the web messenger in a similar way through Windows Live People.
MSN Web Messenger is one of the last remaining MSN branded web applications still available, with other online services such as Hotmail and software such as Messenger itself having moved having moved to the Windows Live brand several years ago, so it's good to see this outdated service finally being retired. As Ars points out, Microsoft Money, Microsoft Encarta and Windows Live OneCare are also all set to be discontinued from June 30.