Consider your music consumption habits before you commit any money to a subscription service, cheap or not. For example, if you like programmed radio such as Sirius XM, Terrestrial/HD radio, or live Internet radio, Napster has nothing to offer you at present. The "stations" that Napster offers (and its Automix function) are more like the seeded Internet radio services such as Pandora, Jango, and Last.fm. They lack the unpredictability and flow of a radio program with a DJ, and draw from a limited well of similar artists. This means that when you select a Napster station, you are likely to hear a number of songs by the same artist in close succession. While this is a useful feature for discovery of new music, those other services do it for free. Napster does not.
Furthermore, even though Napster says there are seven million songs to stream, you'll find yourself frequently running into 30 second clips instead of full songs. In Betanews tests, one search in three yielded an album with only clips instead of full tracks. If you want to hear one of those full songs, you have to buy the MP3. Though it attempts to differentiate itself from MP3 stores such as iTunes, Amazon, and Wal-Mart by adding "unlimited" streaming, underneath its subscription veneer, Napster is quite the same as the others.