BlizzCon isn't happening in Vegas this year. Official word says:
We havent announced any details regarding our next BlizzCon -- though we can confirm that it will not be held in Las Vegas -- so we recommend everyone refrain from making any BlizzCon-related travel plans at this time.
So there you have it. Though, I think it's odd a convention center would show "BlizzCon" on the traditional Friday/Saturday dates, but July is way early. Perhaps there will be an invitational? Who knows, just don't book a plan anywhere until Blizzard says it's "go" and you have some tickets.
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