Near the beginning of the episode, Raj's father tells him to gather his friends for some news. Before saying telling Raj he doesn't see his friends, he looks around. Webcams do not work that way. He would not need to move his head around to see if Raj gathered his friends. However, as a novice using the webcam for the first time, this would be a natural reaction to not seeing them in the frame.
Near the end, Leonard says about Sheldon, "I wonder who's gonna tell his parents they're not gonna have grandchildren," but Leonard knows Sheldon's father has been dead for years. Further, he also knows that Sheldon has two siblings (at least one of which does in fact later give his mother a grandchild) who could do so.
When Raj is complaining about having an arranged marriage, he states that he would be married but unable to speak to his wife. Howard then says "it worked for my parents", however, we find out later on that Howard's dad left them when he was very young. Although it wouldn't be implausible that his mother informed him of this glimpse into their personal life.
In the final scene we see the effect of Penny secretly including rum in Sheldon's "virgin" diet Cuba Libre but there is simply no way Sheldon would not realize there was something different in a drink he well knows the flavor of.
Near the end of the episode, Leonard makes a comment wondering who will tell Sheldon's parents that they aren't going to be getting any grandkids. Even though it's the first season of the show, Leonard and Sheldon were roommates and friends before it started. Leonard would know that Sheldon's father died when Sheldon was 14. So, he should not have used the plural word "parents."
Near the end, Leonard says about Sheldon, "I wonder who's gonna tell his parents they're not gonna have grandchildren," In " Young Sheldon", Georgie (Sheldon's older brother) has a daughter. Being Sheldon's roommate for years, Leonard would know that.