Would it be possible to add a 50-key Japanese keyboard like on the iPad?
When writing Japanese, it's more convenient and perhaps more educative (for non-native Japanese speakers like me) to write with true hiragana or katakana keys, instead of romaji keys.
Not sure if it'll fit on small screens, but it'd be nice nonetheless.
I would imagine this is very useful for native Japanese users, since they are much more comfortable with Japanese characters. Especially if the prediction list also does words in kanji (seems it already does).