[Updated to add Substitution section.]
I haven't exactly counted it up, but of the thousands of comments left on Just Hungry, not to mention Just Bento, probably at least a quarter are questions about ingredients or ingredient substitutions. So I thought I might put down what my criteria are for what kind of ingredients I choose to feature in the recipes on either site, especially when it comes to Japanese recipes. [Update added on August 15th, 2008]: I've also added some suggested, and acceptable, substitutions.
japanese ingredients philosophy produce