Hm, you seem to use the . notation as Python uses decorators, but chaining multiple decorators has a very different effect. In python, I'd expect foo.bar.3 to be (foo (bar (3))). In Arc, it seems to do (foo bar 3).
Various languages were represented in the audience. Generally, python and erlang users were less impressed; but users of java and other blubs found a new way in which their language was inadequate :)
Some were concerned about unreadability, and others dismissed arc as impractical, but overall I think people seemed to appreciate the power macros can bring to a language, and how hopeless the situation is for java et al, given their heteroiconicity.