Is Twitter the new Second Life? Tom Hale's Case Study at the Web 2.0 summit

My friend Wagner James Au recently reported in the New World Notes about Linden Chief Product Officer Tom Hale finishing his presentation on the Web 2.0 summit, 'attacking' Twitter. His presentation "Surviving the Hype Curve: A Case Study" warns Twitter that they might also see a backlash like Second Life did.
See presentation for yourself. One important difference between Second Life and any other "hyped" platform like Twitter or Facebook: Immediately perceivable, substantial impact beyond its user base. Yes, Second Life is still growing and yes, its users, the residents, are very loyal, once they stay for longer, but outside the virtual world, the impact is not very feasible.