With WWE officially announcing that the WWE Network will be launching next year, fans have been talking about what content will end up filling out the schedule. WWE has bought up many video libraries over the last several years, to the point that airing all of it with no repeats would take about a decade.
It's unclear if all of the footage is ready to air. WWE released statements years ago about having a Japanese company digitize the whole library (which consists of a huge mix of films and many forms of broadcast quality videotape, some of which are in very antiquated formats), but now they're saying that not everything is ready.
Going by recent comments, I'm under the impression that they're going through the process of upconverting the standard definition content that makes up the vast majority of the library to HD. They also haven't indexed the whole library to their satisfaction.
WWE has a ridiculously detailed database of what happens when in everything they index. Everything that could be relevant (specific moves or other actions performed by wrestlers) is logged with time stamps. This is how WWE is able to put together old video packages of similar clips so easily.
At any rate, they still have a lot done, though there's no telling how much has been digitized from each library that they own. Let's take a look at each library that WWE owns and what you can expect to see from them, as well as quick looks at each of the major remaining libraries that they haven't acquired.