Immediately before Michael and Kit lie down under their first Christmas tree, there are several presents underneath. When they lie down, there are no presents.
Kit's parents SUV has front license plates which are not required in Pennsylvania.
During the last Christmas, RuPaul's Drag Race Holi-Slay Spectacular (2018) is being shown on TV years before it's actual release in 2018.
After Kit is hospitalized from appendicitis in 2003, he asks Michael to clean-up his apartment before his parents arrive. Inside his apartment are several DVDs on a shelf, two of which featuring The Criterion Collection's 2006 cover redesign.
At 39:27 in the video, Kit says "Oh!" but the audio is "Oh yeah!"