Is iTunes a monopoly or a failure? Maybe neither.
It's not a monopoly, says Daniel Eran because similar products are on the shelves right now:
Likewise, there is no scarcity of WMA content that is holding back WMA players. Rather, they are simply not selling because they are poorly built, and poorly marketed, and have a feature mix that gets all the details wrong. They fail to provide what consumers demand or anticipate features they will find useful.
And it's not a failure either:
Somewhat ironically, the same bloggers who like to worry about an iTunes monopoly were quick to jump on a report by Jupiter Research with data that found the average iPod user in Europe had only bought 20 tracks from iTunes. Does that mean the iTunes Store is a failure headed nowhere? ...Mulligan [of Jupiter Research] found that while few music player owners were regularly buying music online, iPod users are more likely to buy legal music downloads than users of competing products, particularly the WMA platform. In other words, the emerging market for digital downloads is brand new, and Apple's clearly leading it.
What are some of the reasons iTunes has been successful then? Eran lists the following as possibilities: