here a article from yahoo news:
http://hk.news.yahoo.com/041229/197/181ng.html
it basically mentioned about her 4 No.1 albums and her american carreer...
last sentence:
目前她正計畫明年夏天再度推出日語專輯。
translation:
currently, she is planning to release her Japanese album in summer next year (note: the date of this article is 30 Dec 2004)