I found the Rails implementation of MVC to be the easiest to learn of the 4 I've worked with (.NET, CodeIgniter/Kohana, Rails, ObjC), followed by CodeIgniter/Kohana. Rails made it clear from the very start with its "Everything is an object" mantra that I could always expect to things to just work if I treated everything like an object, and did a great job separating the three components of MVC. My views in Rails have always looked a whole lot cleaner and simpler than NIBs or .aspx files or even the CodeIgniter view files.
However, I must say I can work a whole lot faster in ObjC now, mostly thanks to XCode's awesome debugging tools.