Among the slew of announcements by Microsoft, MSN Music is perhas the biggest one for music companies: the MSN Muisc store has been formally launched, here...it has added a bunch of new content, added music news, added audiobooks, ringtones, videos, Billboard charts etc…

It has also launched music stores in Austria, the Netherlands, Spain and Switzerland, though a partnership with Loudeye’s OD2... Services in Denmark, Finland, Norway and Sweden are coming soon through a relationship with CDON.

The music store will be in 18 markets by the end of the month, the company says….

Also make sure to check PlayForSure, for portability info on MSN msuci and other services…

Update: Also make sure to read Neowin’s review and interview with Christine Andrews, Lead Project Manager at MSN, about the launch and the development of MSN Music. “MSN investigated the possibility of acquiring the Beatles catalog of music. The potential terms of the discussed agreement were unattractive at the time for various reasons.”