ARGs are the new black - discuss

Writing at Museum 2.0, Nina Simon describes the use of an alternate reality game at the Smithsonian American Art Museum (SAAM), An ARG at the Smithsonian: Games, Collections, and Ghosts.  I can't comment further in any detail since I'm not really into this kind of stuff but one of the things I sensed at ALT-C 2008 was a distinct and growing interest in ARGs as a learning tool - are we in the early part of another hype curve here?

Interesting to see museums playing in this space - are any UK museums doing this?