We'll keep an eye on what's happening here on this post -- feel free to comment if you're waiting for tickets, and if we see the sold out sign (or a notice from Blizzard that they're all gone), we'll let you know when to refresh. We don't know exactly how many tickets Blizzard wants to sell tonight, but we know it'll be less than they've sold so far, and actual selling time is less than an hour or so by our count. So these will likely go fast. Updates after the break.
Update: At 11:21pm, the main site is reporting that tickets for BlizzCon are completely sold out.