Caution for Professionals on OS X Yosemite
Coverage of OS X Yosemite is over at my MacPerformanceGuide.com.
Professionals using Photoshop, Maya, Autodesk, Unity, etc should proceed with caution towards OS X Yosemite. It might not be ready for prime time.
I am experiencing my own severe performance issues with Yosemite, in of all places, the File Open and File Save dialogs (which I use hundreds of times a day, so this is a real time-waster in my day).
See also OS X Yosemite: Screen Bleed-Through for Images Impairs Perception.