Looks like Drysc is right on the money. Just a few hours after letting the World of Warcraft community know that there were still ample supplies of the BlizzCon event's coveted admission tickets, the Blizzard rep dropped by the WoW Forums once again to let everybody know how the sales were going:

Approximately half the available tickets for BlizzCon 2007 have been sold in the first 24 hours, and they're continuing to go rapidly. If you plan to attend, we recommend getting your tickets quickly, as they are likely to sell out soon. We thank you for your enthusiasm, and look forward to seeing all of you in Anaheim, California on August 3 and 4.