I cannot figure out how to just practice the Japanese kana. I'd like to be able to start with that and then move to kanji when ready - keeping that separate fro words per se.

Unfortunately Skritter doesn't support practicing Kana yet. It is a mightily hard task to write good handwriting recognizers for Hiragana and Katakana strokes (hiragana especially). Right now Skritter only lets users write the Kanji.

Upon hearing this, a friend of mine who is learning Japanese said "ok, I need to learn the kana right now, so drop me a line when Skritter can ride the hiraganasaurus." We're looking forward to that day, but given our current development schedule, it could be a while.

While we won't be able to do *writing* practice with hiragana for the foreseeable future (probably katakana is doable in the medium future, and hey, those are the ones everyone forgets anyway), we could probably set up some reading practice, in which case you would be shown the character and have to type in how it's pronounced. I'll talk with Nick about setting that up sometime cause I think that would be good to have.

I think a lot of people go into Japanese thinking that the kana are going to be difficult, but seriously, it's a day's work to learn them initially, and a week or two of practice to maintain them. I doubt it would be worth the development time to support something that students pass through so quickly.

Perhaps. The katakana will be much easier to write recognizers for, so I'll probably do them at some point.

Users with iPhones should use your KanaTap program instead!
http://globalmaverick.org/tools/kanatap

Cheers for the link! I would tend to agree, of course :P