[alexbell]

Grand Central Dispatch, I think you mean. :)

It's on iOS 4+ as well.

[protomyth]

Thanks, I keep doing that with GCD and calling the "First Responder" First Listener. I am glad they ported it to iOS. It really helps to be able to use the same programming structure on both platforms.

I still think one of the agent oriented programming variants might not be a bad way to build parallel programs.