You will need a micro sd (up to 4gb) card. I got a 4gb for 10.00 on tigerdirect.
It works great for music but it does drain a lot faster. If your sitting at a pc just jack the phone in and u will be fine.
Battery life compared to other phones is great though. Right now I'm doing all my surfing, aim/msn, text, phone, music, etc all with my curve. I get up around now with a full battery and I plug it in around noon for an hour then I'm good till like 7ish. For an unemployed guy I use it a lot so that's fucking good.