Sony is going to shortly launch PMA (Personal Music Assistant) for mobile phones with TeliaSonera with other operators to follow later.
The idea is that you get FM quality music streamed to your handset over either a 3G or a GPRS connection. I think this sort od idea, in reasinably priced, is going to be very popular. Personally I dont want to store vast amounts of MP3 (or whatever format you prefer) on expensive memory cards on my phone. Because the music is stored on a server somwehere you have instant access to a much larger choice.
PMA has things like personalised and channel playlists so what you effectively get is something like Napster 2.0 for mobile phones.
I guess the big thing here will be cost. I guess I'd be willing to give up 10 ish a month for umlimited usage if it works well. I'd prefer something around 5 for say 150 hours usage though.
This presumably ties in with Sony's msuic download strategy that has also been recently announced.