Investment analysts have been talking about Mac OS X as a mega platform. I haven't attended any Mac developer conferences, but when I attended Next Computer seminars the pitch always centered on the object-oriented framework. I don't imagine the pitch has changed much, especially since the Cocoa framework has become easier than ever for developers to leverage when building new apps.
Several years ago, I wrote about the benefits of OS X -- and the Cocoa product platform. We're seeing the benefits grow because Apple is using a slimmed down version of OS X and a new user interface with the iPhone. The framework for the ten-story OS X building has been in place for some time, Apple is simply finishing out the top floors.
I'm not sure what a mega platform is, however, I do know about product platforms. Google's File System is a product platform. Interesting to see that one of the key apps on Apple's iPhone is Google Maps. It's likely that Google Maps is built on top of the Google File System. What's more, Google is working with Apple on other projects. So we have the best product platform for the client combined with the best product platform for the Net.