While Blizzard has made no official announcement, we believe this means that a digital version of the Collector's Edition will be available containing only the digital parts of the CE. The box shown looks like the Collector's Edition box, which lends credence to this hypothesis.
We know nothing (unfortunately) about the release date, pricing, or if this will even exist. But if this is showing up on the Battle.net site, it seems likely.
It's open warfare between Alliance and Horde in Mists of Pandaria, World of Warcraft's next expansion. Jump into five new levels with new talents and class mechanics, try the new monk class, and create a pandaren character to ally with either Horde or Alliance. Look for expansion basics in our Mists FAQ, or dig into our spring press event coverage for more details!