borisyankov/DefinitelyTyped — pull request #31 by BreeeZe (2012-10-30 10:46:13+00:00)
Title: Added KnockoutObservable interfaces for primitive types

For instance, if you assign a variable using "ko.observable(bool)" the return type will now be an KnockoutObservableBool enforcing setting and getting bools only.
The original is retyped as a KnockoutObservableAny which still supports the 'any' type.