Maybe arc could also provide online code upgrades as well.
I like the idea of qualified names (namespaces for things) but prefer it to be divorced from the name of the resource where you find it. For example, in Perl and ruby I can require 'coolstrings.rb' which doesn't have anything to do with a "coolstrings" namespace or class but does change the way strings behave. It also provides a way to elegantly implement pragmas.
Live code upgrades is a great feature. Lisps already support this to some degree. If you make an app and expose a REPL on some local port then you can recompile functions on the fly. I'm not sure how it handles the current execution stack when this happens though.
