I think I'll just make a big list of one-word/short-phrase answers
...
- UMS
- Good sound quality
- line-out
- line-in
- built-in mic
- recording
- radio
- no need for stupid add-ons for things like recording and radio
- wide codec support
- USB-OTG
- M3mod
- inskinning
- possible to replace battery/hard drive
- decent battery life
- nice colour screen
- stylish (IMO)
- and finally...
Rockbox!