Leonard's Valentine's dinner with Penny is sidetracked by Howard and Bernadette tagging along after a mishap with Howard's present. Also, Penny is distracted by one of her exes, who gets engaged a few tables over. Meanwhile, Sheldon enlists Alex to help find a Valentine's present for Amy.
"The Tangible Affection Proof" balanced storylines well. Sheldon's present to Amy, making her his emergency contact person, was meaningful and nicely turned on its head by how many "emergencies" Sheldon has.
Leonard and Penny's storyline delivered, too, Penny's ordeal bringing up her fear of commitment. I'm not sure Leonard's solution relieved any of the pressure, but that's a good thing, dramatically speaking.
Finally, after a rallying speech at a Lonely People's Party at the comic book store, Raj asked a girl out, and she accepted. According to next week's log line, though, the date doesn't go well.