When people watch TV with a hard disk video recorder, they always watch the show delayed, often by hours or many days. They all watch it at a different time.
It occurs to me it would be amusing to generate a system to allow the collaborative annotation of TV programs and DVD movies using the net, and DVRs like the open source MythTV, which would be a natural initial platform. Users watching a show would be able to make comments at various points in it. Either text comments, along the lines of "Pop-up Video" or even voice comments and jokes, along the lines of "Mystery Science Theatre 3000."
And indeed, people already do this real time. Just about every popular show generates a chat-room for people who watch it live near a computer. However, these are usually quite inane as they are done in real time with no filtering.
Thanks to delayed watching, we could change that. Each suggested annotation would be uploaded quickly to a server handling the particular TV show or movie. This would come with a pseudonym for the author, which would be tied to a reputation. All annotations would be sent out for viewing by a limited audience. For low-reputation contributors, a very limited audience. If that audience hits an "approve" button on their remote when they see the annotation, it would improve the score, and more and more early watchers would get to see and approve/disaprove of the annotation.
Eventually things would build up and you would have a series of highly approved comments for those who want to see a show with comments. I expect most comments would be jokes, but some would also be pointers to useful information or reasoned criticism. Authors might indicate what their goal is so that viewers could tune what sort of annotations they want to see. Viewers could also tune a threshold for how good the annotations have to be to see them.
Authors would indicate if their pop-up should show in a particular place on the screen (so that. like pop-up video, it doesn't block things.) Some viewers, especially those with big screen TVs, would shrink the image and redirect pop-ups outside the show.
However, there are some interesting problems to solve...One of the toughest is abuse. Sure, you will get people who will be annoying trolls and pains in the ass, and of course spammers. Fortunately, a reputation system and the fact that only a few people see new comments makes spamming not very productive.
There is one nasty exception -- spoilers. While we would actually allow well-marked spoilers to appear (and most people would turn off seeing them) there will be people who, just to be annoying put in comments that spoil a show. You can't fix this for the poor soul who sees this, even though they get to declare it a spoiler. As such, people with minimal reputations might find that only one or two people see their comment until it is cleared as a non-spoiler. This delays their contributions, but so be it.
As noted, I suggested there could be audio commentary -- and even video commentary from the dedicated critic. We would insist that any audio commentary come with text for those who do not want to turn on audio. And feed the audio comments to just one speaker in a surround system and let the user adjust the volume cap. While text commentary would be small and a single site could handle very large numbers of people picking up the text comments, audio commentary, even encoded with Ogg Speex, would be pretty large. Here, a Peer to Peer distribution system could make sense. Or the author of an audio comment could be required to find hosting for it. Either their own server, or some willing 3rd party who fnds them funny.
As noted, you will either love this or hate it. Even as the person proposing this, I would not want it on most shows, or would tune it to show only the most highly approved comments, and perhaps only the serious ones if I'm not in the mood for jokes.
There are other technical issues. Programs that are broadcast in different places may have different commercials in them or different edits, making exact timestamps hard to do. (If everybody watches the same feed, as in satellite, this is not an issue.) One trick, for closed caption programming, would be to sync the comments to the closed captions, as in "Caption 'x' plus 3 seconds" which should remain accurate even on programs broadcast on different days. Failing that a map of scene changes could be used. In some cases though, you would not be able to use commentary that came from people watching a different feed.
For DVDs it's easier, as there are only a few different DVD editions usually, and the timestamps can be quite accurate, allowing long-lasting commentary. At least for those who have a computer as their DVD player, as I do. I realize that's not so common right now.
Comments could also include screen pointers. An author might provide a comment and also want to circle something on the screen, or point an arrow at it. A simple graphics overlay could do. However, people wanting this would face a higher moderation barrier, as it's more intrusive.