Looking to get it straight from the horse's mouth? Tune into Apple's livestream. But be forewarned — you'll only be able to load the video if you meet these conditions:
Live streaming video requires Safari 5.1.10 or later on OS X v10.6.8 or later; Safari on iOS 6.0 or later. Streaming via Apple TV requires second- or third-generation Apple TV with software 6.2 or later.
In plain English, this means you must be using Apple's proprietary Web browser on one of these mobile devices, on a Mac running OS X Snow Leopard or higher, or a second- or third-generation Apple TV.
Apple's livestream is usually pretty great. But last year it saw a few problems, such as a foreign-language voiceover that made it impossible to hear the presentation. Here's hoping this time goes a little more smoothly.