I'll grant that Sproutcore (and Cocoa for that matter) actually have a lot more in common with Fowler's Passive View (which I've usually seen implemented as a MVP rather than MVC) than the original Smalltalk MVC. But it surely has much more in common with the Smalltalk MVC than the Rails MVC. The only real difference is the composition of the pattern. The Smalltalk MVC is composed of Composite (View), Strategy (Controller) and Observer (Model), whereas the Sproutcore MVC is composed of Composite/Command (View), Mediator (Controller) and Observer (Model). They both manage state through a very similar three tier architecture.