Earlier today we went over some of the options for attending BlizzCon when you can't actually attend BlizzCon. Mainly this consists of the DirecTV-sponsered stream, which is $40 pay-per-view both on DirecTV and over the Internet (even if you're not a DirecTV customer). The BlizzCon tournaments will also be streamed for free.
Here's an additional perk on the Internet stream: if you can't be at your computer right when the events start, you can see it on-demand during and after the show (the Blizzard folks are calling it "rebroadcasting"). This might also be handy if (as a purely hypothetical example) someone needed to review footage to confirm the details of a breaking story for a certain blog that is going to have all the BlizzCon details as they happen.
In fact, ideally, they'd give us full DVR-like capabilities on the broadcast, although I recognize that there's a level of technology required to support that. Still, it would be nice.