First Date - S7-E14
Other mistake: When Buffy, Spike and Principal Wood are driving, how does Principal Wood notice Spike in the rear view mirror if vampires don't cast a reflection?
Lies My Parents Told Me - S7-E17
Other mistake: Robin uses the song that Spike's mother sang to him to provoke him into attacking him. The song is played on his computer through Apple's media program "iTunes". He clicks his computer's mouse to start the song, but when we see the monitor the cursor isn't placed on the Play button. Robin doesn't jostle the mouse when he presses it, it remains completely still on the desk. And the only way to play a song through iTunes using a single mouse-click is by clicking on the Play button.
Chosen answer: Angel is saying that he is still jealous and Buffy recognizes that this is his way of saying he wishes that they could be together. That is why they both smile.