Since OSX 10.6.2, Apple have allowed you to pick 1080/24p as a output refresh rate if your TV reports it is capable when negotiating over HDMI with a Mac. TV's that are 24p or similar mode capable, run some fancy frame trickery on 23.976fps video to smooth out playback. If this is not possible your TV will conduct a 3:2 pulldown of the 23.976fps video and juddering will be noticeable on camera panning for those that are susceptible.
Even if you run your OSX desktop at 60Hz, XBMC or Kodi these days is smart enough to signal the TV to switch refresh rates at the start of video playback. Your TV has to be 24p, 50Hz and 60Hz + more - capable and negotiate properly for this to work. You can even force different OSX refresh rate output by using SwitchResX.
Perfect 23.976fps video sync with a similarly capable TV was not possible on Intel machines until a bug was fixed in Haswell microarchitecture. That fix really is for the ultra fussy video purists. Ivy Bridge pretty much fix the issue anyways.
So summing up. If you have a 24p or similar mode capable TV play 23.976fps video and you set:
Settings > System > Playback > Adjust display refresh rate to match video > On
You will not notice any skipped or dropped frames (they will be rare if at all)
Similarily if your TV is not 24p mode capable and you set:
Playback > Adjust display refresh rate to match video > Off
Sync Playback to display > On
-A/V sync method - Video clock(resample audio)
And you play 23.976fps video on a 50Hz capable only display, Kodi will speed up the video to 25fps, and resample the audio, which will then have a higher pitch.
A 60Hz capable only TV will give you the infamous 3:2 pulldown and the video judder that the susceptible complain about.
BTW I hate how Netflix outputs their 23.976fps video and uses a 3:2 pulldown to display it on my Chromecast.
(yes I'm susceptible to video judder)
Google and Netflix should be shot for allowing a video display device in 2014 to be compromised in such a way, but then I have not seen a device playing Netflix video yet that refresh rate switches to 24p.
50Hz catchup TV output at 60Hz here in Australia looks plain terrible too.
Clear as Mud ?