"... Why doesn't someone make a webapp for the cooks out there who have old, falling apart recipe books to enter in the recipes and store them online? The social aspect of the site is obvious too. It seems like the market is pretty big: people that like to cook ..."I've been looking at this area for a while.
Not to build a business, but interested how you could apply this to recipes, cooking and food. http://www.opensourcefood.com does a good job. so does Jamie Oliver ~ http://www.jamieoliver.com/recipes/ There must be some other angle these to improve on these sites?
One idea I can think of now is to create the "YouTube of cooking demo's". Restrict the time to blocks of 90's of video instruction per user (like flickr) - a section for ingredients another for prep, the cook, and finally presentation. Then see what other users can upload. Maybe a "how do you do this segment" for basic cooking tasks, different cuisines etc. Gradually building up a catalogue of rated segments a user can choose to view.
If I've learnt anything about recipe books, websites is they are inanimate and unless you are determined you can stuff things up. TV comes up trumps. An online video collection of recipes just might improve on TV.