Factual error: Rube refers to Bacchus and Neptune as "Greek Gods" - in fact, they're Roman (the Greek equivalents being Dionysus and Poseidon), which Rube (being well-read enough to mention them in the first place) should know.
The Ledger - S2-E2
Continuity mistake: When Rube is going to give his keys to George, Daisy has a cup in her right hand, at her lips, and is looking at George. Next frame, opposite angle, she has the cup in her left hand, at chest level, and is looking at Rube. (00:14:20)
Continuity mistake: When Daisy takes Stan to church, she takes a seat in the fourth row and sets her purse down. After the window breaks, she runs outside, leaving her purse in the pew. When she returns to find Stan gone, the purse is in the fifth row.
Continuity mistake: At the beginning of the episode George is wearing a sweater that is stained with large blood splatter. During the actual reap she is splattered with blood but the pattern is very different, both in quantity of blood and the splatter locations on her sweater.
Continuity mistake: In the airport, when Mrs. Thibideaux (Roxy's reap) sees the cluttered luggage holding up her suitcase, she climbs over the first few bags and tosses the others down. Before she even started climbing, the conveyer belt was stopped which meant the luggage that she climbed over (including what looked like a bag with skis) would still be in the way. Yet when she falls, it's a clean slide down to break her neck.
Other mistake: When Rube is searching the hard-copy (paper) archives, the young man with him opens the last box and pulls out an old "Wanted" poster with Rube's face on it. He tells Rube "This guy looks just like you." Since season 1, episode 1, we've known that Grim Reapers don't look like they did when they were alive (i.e., Millie/Un-George). Yet somehow, Rube has not changed since his life/death.
Continuity mistake: Near the beginning when Mason takes the notebook from Roxy, the camera is off the corner of the table showing all four seated at the booth. Roxy reaches across the table with one hand and for her gun with the other and starts to explain she will shoot Mason. The camera moves for a close up on Roxy and her hands are now in front of her, folded on the table.
Continuity mistake: In the bar, just after Ray lost a pool game to Mason, they are watching a boxing match on TV. Ray begins to rack the balls and pulls out 4-5 balls and places them in the rack. The camera switches back and forth, Ray again pulls 4-5 balls out and racks them, but the original ones are gone. The camera switches back and forth again and when Ray is done racking the balls, the balls are in a different order than he placed. He is watching Mason, not looking where he places the balls. Watch the 2 and 11 balls.
Audio problem: When Daisy is at the bar (acting), she gives Walter "5 reasons men come to a bar." When she says "Three: They wanna see that they're missing," her lips are not in sync with the words. It's tricky to see because they used a shot with the camera behind her.
Continuity mistake: When Rube's talking to the graffiti artist, he's painting what looks like a blue cat. We cut away, hear a brief paint spray, then cut back. There's now far more painted than that spray could have achieved, and what was there already has changed as well.
Continuity mistake: When Daisy is in the diner with the other reapers talking about her acting job, the fruit in her hand changes from a red grape or cherry to a green grape.
Other mistake: When Mason is punching the air and Nina imitates him the chair wiggles with the motion of her body but since she is dead she would pass through it.
Continuity mistake: When George writes Nina's name on the sticky note she holds it up and we see the writing is small but then we see a close up and the writing it bigger and the handwriting is a little different.
Revealing mistake: In the scene where Monteleone falls off the wall, the stunt double is visible. Watch the hair color.
Chosen answer: The Song is Callled "Boom Boom Ba" and is by the band Metisse. it plays at certain points during the series. Mainly when George is looking over Reggie or in Reaping Havoc where it plays whilst shes showing her scrapbook "Mysterious and Reassuring" which is what she thought Betty was.