I think the only reason Utada would perform any Japanese songs on her tour would be because of taking requests. Of course, if she took requests, we all know people would scream "Kingdom Hearts!" for the fans of the video game and "Boulevard of Broken Dreams!" for the youtube watchers... and she probably even forgot that Green Day song by now (in a radio interview covering her TitO album, a listener asked her to sing Simple & Clean and Utada said herself that she nearly forgot the words to her own song).

This isn't a full-blown mega-tour like Britney Spears or Beyonc?, and I don't even think her tour performances will last for very long. I theorize that the only songs she will sing are from TitO, and MAYBE one or two from Exodus like she did in her Utada United 2006 Japan tour... but that's it, other than possibly taking requests for songs.