As Howard reads the text from Lucy, and then Raj leaves the room, Howard is holding the cell phone in his left hand and his drink in his right, and Howard is looking at the phone. It cuts to Sheldon to say it didn't kill him when Howard went to space, and Howard is staring straight ahead. It then cuts back to Howard and the cell phone is now in his right hand and his drink in his left.
When Sheldon is giving Leonard factoids to make Leonard not want to go on the boat. On the left side of the screen, in the background outside the car, a man appears at a garbage can despite a fluid scene. Clearly the man wasn't there, but is now.
When Leonard is driving Sheldon in his car, the closeup shots all reveal a dirty windshield outside of the wiper blade area; however, all of the wide shots, except for one, show the windshield as completely clean.
Jim Parsons can briefly be seen to break character. The scene just after Raj Skypes his girlfriend is the party scene in Leonard and Sheldon's apartment. As the camera pans across the group, Sheldon, Penny and Amy are talking in the background and suddenly Sheldon breaks into a very non-Sheldon chuckle moment with Penny.
Sheldon (again) refers to his trivia items as "factoids". Sheldon is a pedant who would know that the original meaning of factoid, as coined by Norman Mailer in 1973, was a small piece of information which appeared to be true but which was not. Its newer meaning (any small trivia item) was popularized in the 1980s and would have annoyed Sheldon the Arch Pedant.