From my experience, they've always had graphics driver issues since the early days of Mac OS X.
Or more like a conspiracy (in b4 Taz Mangus says it's a comspiracy
) to make sure you keep buying their hardware every 2 years or so if you want to have the greatest UX. For my current hardware, a mid 2010 MBP, Mavericks and Yosemite UI runs like crap at times. Both suffering from video playback stutter due to intermittent but intensive background resources. The only good OS X to fallback to is Snow Leopard which came with my MBP, that's about the only way to retain GUI fluidity.