My full-screen Netflix (using Safari) is still doing the weird swiping movement. I have an appointment at the Apple store tomorrow, will let you guys know what they say.
Edited to add: on my other post about this issue, I received this reply...
Hi Rachael122,
Thank you for visiting Apple Support Communities.
It looks like your screen sometimes shakes when watching videos in Netflix. We can offer some troubleshooting steps that may help now or in the future.
Does this happen with other movies? You can test by downloading a movie trailer or past purchase from the iTunes Store to see if that plays normally in full screen. See Download your past purchases.
If you see the same behavior with other video content, you may want to try again in a new user account on your Mac. This can help rule out software conflicts or other issues: How to test an issue in another user account on your Mac
If this is isolated to Netflix, you can find some specific information that may help in The Netflix player is off-center when I try to watch.
All the best.