If GPRS for Data is so expensive, then why would anyone want to use it, especially for large files, video, music. This is exactly why the hybrid GSM/WiFi phones are so crucial. Go to a Starbucks hotspot, suck down your coffee and your content at the same time.
Why do I say Starbucks? Well they already have the music, the relationship with T-Mobile. The customer base and the technology elements to make it happen.