Can someone tell me the difference between “intense sequences of violence” and “strong bloody violence”? How about “grisly bloody violence” and “strong sadistic horror violence”?

Here’s another. Parse for me, please, the distinction between “sexual material” and “sexual content.” And this, my new favorite hair-splitter: “brief smoking” versus “momentary smoking.” What’s the difference there, three puffs? Two? How little on-screen smoking would have to take place for the smoking to be designated “fleeting”?

Each week, in its ongoing campaign to become sillier and more perplexing, the Motion Picture Association of America’s Classification and Rating Administration (MPAA and CARA for short) contributes another series of film ratings, along with reasons, briefly (or “momentarily”) stated, for those ratings.

What do Wall•E the robot, Remy the gourmet rodent and Jason Bourne the assassin have in common?

No, they don’t all love “Hello, Dolly!” As far as we know.

No, they’re not all wizards in the kitchen. When does Bourne have time to cook? He’s too busy running.

The correct answer: This summer’s “Wall•E” and last summer’s “Ratatouille” and “The Bourne Ultimatum” belong to the $200 million club. Different as they are—two are from Pixar, one is a franchise entry made by a first-rate director—each of these excellent, expensively produced pictures grossed a bit over $200 million domestically.

For a while now, I’ve wondered if certain films (good ones working outside the usual parameters) are simply destined to hit that invisible $200 million ceiling here in North America, while eyeing the international market for the real bacon.

When all is said and done and wrapped up in Spandex, “Mamma Mia!: The Movie” will do a great deal for the financial health of the movie musical genre. (Coming soon: “Chicago” director Rob Marshall’s version of “Nine,” starring Daniel Day-Lewis.) Nearing the $150 million box office mark internationally, the film version of the ABBA-laden stage hit is guaranteed to outperform such solid successes as “Hairspray” and “Dreamgirls.” Even if it never catches up with the international $300 million gross of “Chicago,” it’s a hit. A big one. It’s like the stage show: Lots of people are going twice, three times.

I’ve taken more poop for my review of “Mamma Mia!” than anything this year except “Indiana Jones and the Kingdom of the Crystal Skull.” Let me answer certain recurring charges.

Do I hate musicals? Please. I’m the sole heterosexual member of the Dolores Gray fan club. It’s the genre I cherish most. I’m teaching a class on Vincente Minnelli this fall at the University of Chicago Graham School, downtown at the Gleacher Center.

This summer, in terrific films and craven ones, violence threatens the populace. Why should this season be any different? Think of the Joker, fomenting terrorism and nerve-racking pathology in “The Dark Knight” (terrific). Think of Angelina Jolie slaughtering all those deserving losers, or James McAvoy shooting the wings off a fly in gargantuan computer-generated close-up, in “Wanted” (craven). Think of Pierce Brosnan slaughtering “SOS” in “Mamma Mia!”

Now that “The Dark Knight” is on its way toward sleek Goth superstardom and enormous profits, it’s a good time to note that not everyone is in love with its nightmarish vision of a world without order. There are those who find its aura of foreboding and free-floating menace, spiked with some outre acts of sadism (the Joker’s disappearing-pencil bit, over in an eye-blink but striking nonetheless), too much for the comic-book genre, too much for the “Batman” franchise, too much period.

It’s certainly too much for kids under a certain age. Eleven? Twelve? Or 13, as suggested, in its unenforceable, just-a-thought way, by the PG-13 rating?

The decision is personal. All I can do is suggest you be careful with this one, though on one of the Tribune comment boards, Tom from Libertyville shot back: “How can you say it’s not for my kids? Stick to parenting your own children and stop siding with the ratings board.”

If you've seen "The Dark Knight," you no doubt have questions--about the plot twists, the Chicago settings, the technology ... We're building a "Dark Knight" FAQ to take your questions -- answer what we know and let you help us expand on the answers. Post your questions in the comments on this post and look through the other "Dark Knight" posts on Talking Pictures to see them answered (or answer some yourself). Caution: Spoilers galore!

Is Gotham City orginally supposed to based on Chicago? A couple of my friends were sure of it, but I thought Gotham City was just an ambigious city...kind of Springfield in the Simpsons...

(submitted by Nicole)

We'll jump in on this issue soon. In the meantime, what do you know about Chicago as Gotham City?

What's with the buzzing? The movie begins with a vague buzzing sound -- like distant construction work -- that recurs in many scenes featuring the Joker. Was that deliberate, or was it just a lousy sound system in that particular theater? Any insight on the soundtrack choices for the Joker's scenes?

(question submitted by chicagotribune.com producer Charles Meyerson)

While we work on an answer, let us know if you know what's up with the buzzing!

Q: In "The Dark Knight," the Joker and Batman square off in a half-finished skyscraper. Where was that filmed?

A: It's actually a composite of sound stages and two real locations in Chicago: 505 N. McClurg Ct., a condominium construction site, and Trump Tower (401 N. Wabash).

(answered by Tribune reporter Robert K. Elder)

Q: What villains are left for a sequel?

A: Good question. While the Penguin, Poison Ivy and the Riddler remain mainstays the Rogue’s Gallery, they seem a little too campy for director Christopher Nolan’s vision of Gotham City. There’s also drug-fueled muscle man Bane, who made an appearance in 1997’s “Batman and Robin,” or the bandage-faced Hush, a relatively new villain. There’s always Catwoman, however. The rooftop hopping jewel thief might be the perfect foil, and possible love interest, for Batman.

(answered by Tribune reporter Robert K. Elder)

Q: Was “Two-Face” Harvey Dent (played by Aaron Eckhart) a villain created for “The Dark Knight”?

A: No. Actually, Two-Face has been a part of the Batman cannon since 1942, when he appeared in Detective Comics #66. Gotham’s District Attorney turned crime boss was previously played by Tommy Lee Jones in 1995’s “Batman Forever,” and by Billy Dee Williams in 1989’s “Batman,” though Williams’ version of the character had yet to become Two-Face.

(answered by Tribune reporter Robert K. Elder)