official news is out regarding a North American release for Dragon Quest IV, in the form of the official website. The site doesn't have much information up about the game -- except its release date, September 16. English screens and stuff can come later!
The real news is on the new Dragon Quest series site, which shows pretty unambiguously that the Dragon Quest V and VI remakes are on the way as well, with matching alliterative subtitles (Dragon Quest V: Hand of the Heavenly Bride, Dragon Quest VI: Realms of Reverie). This will be the first U.S. release for these two games (IV was released on the NES) and their availability will mean that, for the first time since IV, every main Dragon Quest game has had a U.S. release.