I was just reading through old Exodus reviews and I came across a point in the USA today review where the reviewer states that Hikki has 'vocal limitation' which in my oppinion are one of the only things that no one can criticize about Hikki. full review below.
Utada, Exodus (* * * ) On her U.S. debut, 21-year-old Japanese superstar Utada Hikaru crafts slick, electronically fueled tracks that could, on their surface, pass as background music for nightclubs and loft parties. Luckily, this young singer/songwriter is more than a ghost in her own machine. Like the young Madonna, Utada projects a girlish yearning that transcends her vocal limitations and melts the cool sheen of her arrangements. Tunes such as You Make Me Want to Be a Man and Let Me Give You My Love cannily blend dance, R&B and Asian textures with a soulful spark, proving that hipness and humanity aren't mutually exclusive assets. ?Elysa Gardner
tada projects a girlish yearning that transcends her vocal limitations

Otherwise I think it is a fair review......