Sweeping iOS 7-style changes said to be coming for OS X 10.10 (arstechnica.com)

This would only make sense. They bought the "app store" to OSX and then brought "apps" as well (for some odd reason, people thing apps are different than applications)......

Bringing the two OSes closer together would mirror moves by MSFT where W8 and Windows Phone 8 have similar looks.