Shoutbox

Not true, windowhooks, button hooks, complicated ASM hooks, all not possibly from script. vikke is right about that.
I don't deny that scripts have a lot of power, as the APIs that Plus! provides are very very broad, but if those would have been provided to a Plugin system it might possibly be even broader.

And the only way in which Scripts would be able to match the power of Plugins is if you'd write an external DLL to do the dirty work, in which case it'd no longer be a script