On a recent commercial, it showed Google Docs linking to many other things. This is much like a multimedia wiki. The thing is, there is no feature specifically for this. You have to get the link of each thing. So a cool feature would be under link, you can chose to link to other products, and than specifically chose something under each. This feature could start just with Google Docs documents (making it like a plain wiki) than with all of Google Docs products (linking spread sheets, presentations, forms, collections, drawings and documents, which would qualify as a multimedia wiki) and then move to making it easy to link any Google Product to another (linking Social Media, Videos, all that other stuff, search, and more, making it a Super Multimedia WIki.) You must remember that Google is already capable of this with relatively low skill, it just isn't as convent as it could be.