I've already blogged about this in the blurb about the 2.05.00 release, but I thought I'd highlight that there are now some performance results for Theron online.
Although tested on a somewhat humble machine, the results establish Theron's raw performance as being as good as (or better than) well-known Actor Model implementations such as Erlang and ActorFoundry.
(That said, it should be noted that those implementations are more fully-featured; Theron is quite lightweight by comparison and pretty "C++" in its design intentions).
More results, from a more representative four-core machine, to come in the near future.
Story published 3 July 2010.