The Switch element is styled after the iOS 4 and earlier rounded rectangle instead of the round switch used in iOS 5 and later. It's certainly possible to do this newer style using css/js as well and it would help apps built with KendoUI from diverging from the controls used in the rest of the OS. http://css3wizardry.com/2011/12/18/ios-5-style-switch-control/
Styling is updated in one of our current release - Q3 2012.