Valve has recently released a series of teaser videos narrated by Aperture Science CEO Cave Johnson for Portal 2 called the Aperture Investment Opportunities. While the videos don't necessarily reveal much about gameplay, they certainly inspire continued confidence in Valve's sense of dark humor, which was a very important element to Portal's success. My only regret is that there are and will only be four of them: Panels, Bot Trust, Turrets, and Boots. If there was any doubt that Portal 2 would not retain the same level of dark humor, it should be well erased by now.

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