Great thoughts! I've been tossing around some concepts like this in my head for a while, but don't really know what to think of it yet. But you've done such a great job of "getting the ideas on the table" for discussion, which is sometimes the hardest part!
I've been wondering why those adventure games (also called interactive fiction) aren't made for a simpler read, or at least why they don't provide a very helpful hint system in the games.
On the one hand, I think I can understand why few books will have the kind of commercial enhancements you have talked about... a game is generally thought of as a repeatable exercise that's fun even after completing it once. (I'm not really a gamer, so help me out guys... is that right?) But a book is something you generally experience once or twice and are more interested in the core read than the wrapping. That would not provide much incentive to spend time and money with frills. Especially if the particular illustration technology limits the audience.
But, on the other hand, there was a lot of time spent on making books fancy in the paper format for hundreds of years, so why not ebooks? Some books would really find enhancement of the story, like Tolkien's books. Of course those aren't even availble legally in etext form, so I guess that's not likely.
How about Hitchhikers Guide to the Galaxy? Wouldn't it be great to have a version that integrates the BBC video series!!!! Or how about some other classic books for which the pictures already exist? Or even popular sci fi books. Isn't there fan-fiction? How about fan-illustration!? (Someone would need to create a few software features to support that, but people are creative and I'm sure it could happen if there was enough of a groundswell of interest.)
On the other, other hand, though, I'm not really impressed at the way people have integrated multimedia into text. E.g. even encyclopedias or reference books. It seems that it's either not very easy, or no one has come up with the right approach. So maybe it will have to grow out of interaction fiction which may gravitate into "real" books instead of stories written just for that fiction.
Anyone remember a company that did something like that for Palm a while back? I think they did Sherlock Holmes stories, but I can't remember.
Great thread, Team7, and I'm looking forward to other people's perspectives.