MP3 Insider: The iPod phone is here - CNET reviews: "I had an MP3-playing phone back in 2001: the Samsung Uproar. It was available before the iPod was, and it didn't rule out the iPod's success, obviously. Likewise, the Motorola E399/ROKR and the Sony Ericsson Walkman will not eclipse the MP3 player category because people need two portable devices: one for fun (music, movies, and games) and the other for responsibility-related activities (keeping in touch, making appointments, and storing contacts). The reason for this is battery; people don't want to entertain themselves to the point of losing their cell phone. Think about it: Would you listen to music if you knew that meant you'd lose all cell phone functionality after a few hours?"
Interesting... battery life... maybe I should upgrade my phone to a 5 megapixel one instead, this battery problem is a big deal!