We're doing a lot of this (iPad in the kitchen, text-audio-video, moment by moment tutorials w/ pictures and video) over at http://www.onlinecookingschool.com/ -- I encourage you to check it out. Please send any feedback you have my way!
Looks pretty cool. Biggest feedback is to lower barrier of entry by having a step before the 14-day free trial. Maybe you put together a free package that users can get to and play with without signing in. If they want to save their progress then they have to sign in, which starts the 14-day free trial.
Right now the website just gives me the "this looks like a commitment" feeling, which I'd work to lessen since cooking is one of those things where people randomly get on a wild hare and it lasts a few hours to a few days; you have to hook them during that time or their interest wanes and you don't see them again for a few months/years.
