Distributing new versions is an issue though, as there is no way to tell anyone who is currently seeding the old torrent. But it's not a terrible idea if it turns out there is really a lot of bandwidth (I don't expect that), then I could use my server for seeding at least.
I mean, thats essentially the apple app store right? Just with torrents and documents instead of apps? So like a freely distributed google docs, but for everything. That movie you downloaded a week ago got a better version, the sci-hub article you downloaded last week has commentary from the author or has been disputed, That microsoft office (excel, word, onenote) you've been working on with a group has a long revision history and automatic version control. You could even download the 'latest version' at 'run-time'; when you double click to open the document. There's a company, or atleast the very start of one in these ideas.