i went to the otacafe but i was disappointed by the lack of selection. i'm really into j-pop/hip hop rather than just anime themes.. and i asked if i could use my ipod and the staff said no
i thought i had heard that they were cool about doing that?
and also, both times i went they said they were done taking songs for the day (it was a few hours before the convention center closed), but the room looked empty. oh well