Here's a quote from a TechCrunch article about Mac OS 10.7:
The computing world is shifting into the age of mobile, and iOS is now seen as Apple’s major operating system. Perhaps OS X Lion will represent the beginning of a unification between OS X and iOS. And if Apple is giving it the Lion moniker, which they won’t be able to top, perhaps they mean this to be last version of OS X? (Though they do say “next” version of Mac OS X and not “last”.)
It seems really odd to me that anyone would predict that the next release of OS X could be the last. As if everyone is suddenly leaving their desktop and laptop computers behind in favor of their iPhones and iPads. Trying to merge iOS and OS X would be fundamentally stupid. They are operating systems that target different types of devices with wildly methods of user interaction. Sure, it's smart to share some components, but I wouldn't want to run the exactly same OS on my phone and computer.