"My expectation is it could be upwards of 3 million people. I think that's a fairly conservative estimate," Jarrard said. "Certainly there will never be a console beta of this magnitude." That's a considerable increase from the Halo 3 beta, which managed to snag 820,000 participants during its 26-day run during the summer of 2007.
Sure, the inclusion of jetpacks undoubtedly raised some eyebrows, but we would never have thought the potential for atomic teabags would be that big of a selling point. C'est la vie.