The second batch of BlizzCon Tickets will be on sale on Wednesday, May 24 at 7:00pm (Pacific) / 10:00pm (New York). The ticket price is $175, but with the tax it goes up to $190 each. There is a limit of 4 tickets per account.
Make sure to login into your battle.net account twenty minutes prior to the sale, and start reloading the BlizzCon Tickets sale page.
Remember, if you don't get into the queue within the first 30 seconds, chances are you won't get a ticket.
There will be a third batch of BlizzCon Tickets, but that one will be for the exclusive BlizzCon Dinner with the developers and executives at a cost of $500 per ticket. Money will be donated by Blizzard to the Orange County Children's Hospital. The BlizzCon Dinner tickets will be on sale Saturday, May 28 at 10 a.m. (Pacific Time) / 1:00pm (New York).