When Sun and Jin are leaving to go to Locke's camp and Juliet stops them, she says Jin's name to get his attention and he stops and faces her. The camera cuts to Sun's face and then back at Jin, who is shown once again walking and stopping to face Juliet.
Jin previously stated that Sun and Sawyer have been helping him speak/understand English. Yet, he reacts when Juliet says, "Your wife had an affair." Although plausible that Sawyer taught him the word "affair" (we know Sun wouldn't teach him), it's highly doubtful he learned the word and its meaning with his very basic English understanding. However, he first says "What?" and only understands Juliet properly when she elaborates by saying "Sun was with another man."
At around 24:30 after the woman jumps into the ocean, you can already see Michael with a hood on looking into the water. It was revealed a bit later in this episode that he is on the boat.
Jin's actions occur before the plane crash (so before 2004). However, when he goes to the toy shop to buy the panda, you can clearly see the video game NBA Live 08, which was released in 2007.
When Jin smashes his cell phone in frustration, you can clearly see the shadow of the cameraman in front of him.