As has been previously reported, Apple is not merging the two operating systems, opting to keep iOS and OS X as separate entities, but the next version of OS X may share similar design elements with iOS 7.
Apple is targeting the desktop OS for release in the fall along with new hardware that will ship with this latest OS X version. Though the internal development codename of OS X 10.10 is "Syrah," the shipping name is still unclear, with Apple apparently securing trademarks for popular California locations that would match the new theme started with "Mavericks."The new look will have similar toggle designs to iOS 7, sharper window corners, more defined icons across the system, and more white space than the current version. However, OS X characteristics like the Finder, multi-window multitasking, and Mission Control will not disappear in favor of a more iOS-like experience.
On the iOS 8 side of development, Apple is allegedly pushing some features of iOS 8 off to version 8.1 as the company focuses intently on its next version of OS X. Though Apple may present most of the new features of iOS 8 at WWDC next month, some notable additions such as transit functionality in Maps may not be available until later versions of iOS 8.
Apple TV is also now a priority for Apple, with the company rumored to be bringing in hardware and software engineering resources from within the company to work on the next generation device. Apple may be concurrently developing new hardware as well as a revamped iOS-based software system to power the device. Apple had hoped to introduce the hardware in early 2014, but the product's debut has been pushed off. It is, however, unclear whether a new Apple TV will make its way into the WWDC keynote.The new iPhone's larger display, as well as a "high-priority" iOS device that is not an iPhone, also lends itself to another core iOS 8 addition. The feature, dubbed by Apple employees as "multi-resolution support," is designed to improve the performance of both App Store applications and the general iOS operating system across multiple new iOS device resolutions.
Article Link: Apple's WWDC 2014 to Focus on OS X 10.10 as Apple Pulls Resources from iOS 8 to Help