This is what I am talking about, where MS will not be able to leverage their market share. It's true that if they come out with a service that some people will use it by default, but, the numbers will be very small for several reasons:
1. Apple's deal with HP means that even more PC users will have iTunes as the "default" player, not too mention the mind share.
2. Apple's deal with AOL and the integration of iTunes with their service gives Apple access (by default) to millions of PC users. What I mean by default is that clicking on a song link in AOL launches the iTunes player and music store.
3. Apple is getting A LOT of buzz regarding the iPod not too mention the fact that they are selling them like crazy.
4. Anyone who uses Media Player and iTunes will use iTunes. Media Player is buggy, it's user interface is very PC like, and a MS music store won't be any better.
5. BUT most importantly, time to market is a very relevant issue regarding digital music stores. Most people who are now using iTunes will continue to do so; they will not switch. No one will really like the idea of managing multiple DRM accounts for their music. They will pick one service and stick with it. Right now that service is Apple's iTunes music store. Every day that MS delays in releasing a service hundreds of new customers are signing up with iTunes. The game is over already. There will only be a few online music stores in the end and the ones who are playing right now stand the best chance of surviving. MS may release a store but will kill it with their proprietary stance and it will ultimately be too little too late. They will loose money on it and with all their other troubles will just kill it. Throw it in the trash can along with Real. Control Panel > add remove programs > are you sure you want to delete? Yes.