Not to sound like a Muggle, but in a time of “Transformers” and “Twilight,” does Harry Potter still matter?

Is Daniel Radcliffe destined to play second fiddle to Shia LaBeouf or Robert Pattinson as box-office prince? Will it take Amortentia (the world’s most powerful love potion) to make us wild about Harry?

The film took in a record haul at midnight showings Wednesday, but the final answer comes Monday when box-office tabs show just how much staying power “Harry Potter and the Half-Blood Prince” has.

The movie landscape has undergone seismic shifts since the film franchise started in 2001 and skipped through the decade earning $4.5 billion worldwide.

The entertainment world has morphed since just August, when Warner Bros. said it was bumping the sixth Potter movie from fall 2008 to July 2009 and incited angry online petitioners.

A year ago, this was a lucky week for the studio when “The Dark Knight” started its ascent to No. 2 on the list of all-time box-office hits (behind “Titanic”).

Now, “Harry Potter and the Half-Blood Prince” has Voldemort tightening his grip on the Muggle and wizarding worlds, as danger and hormones rage.

After box-office expert Paul Dergarabedian saw the latest “Potter” at an industry preview, he blogged that he was “blown away like a Quidditch player on a supercharged broomstick. …

“I just thought the movie was terrific; I really enjoyed it. It made sense to me. I got involved, I liked the fact that they’re older and definitely more assured in their acting, and even the characters are more interesting,” says Dergarabedian, of Hollywood.com.

“When you have Michael Gambon, Alan Rickman, Helena Bonham Carter – I mean, there’s some great actors in this movie. Robbie Coltrane. It just looks amazing, but it’s more than that,” with a strong humanistic story.

“It reminded me of an old Hollywood spectacle,” he says. “It looked very expensive and very rich.”

It’s a coming-of-age story with humor, heart, budding romances and threads about loyalty and betrayal. A cherished character dies, which readers had anticipated with curiosity and dread.

Not everyone is aboard the Hogwarts Express, however.

Marketing expert Jack Trout from Trout & Partners in Old Greenwich, Conn., says, “I view ‘Potter,’ in some respects, as sort of a fading franchise. I think there’s been so much of it for so long and essentially new things have arrived … and I think a lot of the ‘Potter’ crowd has moved on to vampires.”

The bloodsuckers are everywhere, from the “Twilight” and “Vampire Kisses” books to the adult “True Blood,” the vampire series on HBO. And the marketing expert suggests there’s a point where Potter fatigue – same bad guys, same good guys – can set in.

But Trout concedes, “The fact that they’ve kept it for so long is mind-boggling. Few franchises in show business really last that long.”

“They’ll do fine” at the box office, he says of “Half-Blood Prince,” but adds, “Even Potter grew up, and their marketplace has certainly grown up.”

As for the books, “certainly there isn’t the anxious demand that there was before the seventh ‘Harry Potter’ or the fourth Stephenie Meyer, but we aren’t seeing a real drop-off in interest, and I think it’s because in some cases there’s a new audience coming along every day,” says Lisa Dennis, coordinator of Children’s Collections for the Carnegie Library of Pittsburgh.

If older readers have graduated to other books, a new crop of 8-, 9- and 10-year-olds is taking the plunge. And saying that she was dating herself, Dennis adds that the books remind her of “The Hobbit” and “Lord of the Rings” trilogy in that people love to revisit them.

One series that doesn’t have the same staying power: “The Spiderwick Chronicles,” about siblings thrust into extraordinary circumstances as they lift the veil on a world of faeries.

“The first five books were wildly popular, the movie came out – I think it did OK – but I don’t think it built any kind of a new audience,” Dennis says.

A follow-up series, “Beyond the Spiderwick Chronicles,” did not generate enthusiasm, and interest in the original volumes has cooled.

“There are things that come and go, but I have to say that I think ‘Harry Potter’ and probably Stephenie Meyer’s books are here for some time,” Dennis says.

So are the movies, since Dennis ordered new copies of the previous five for the libraries so patrons can refresh their memories about where they left off. That would be with “Harry Potter and the Order of the Phoenix,” the fifth-highest-grossing movie of 2007.

Circling back to the question of relevancy, Dergarabedian says, “Harry Potter was still relevant in a (2007) world where there was ‘Spider-Man 3’ and ‘Shrek the Third’ and the first ‘Transformers,’ which had come out July 3,” a week before “Potter.”

The law of diminishing returns usually applies to franchises, but some either hold their own or win Oscars, as with the third and final “Lord of the Rings.”

“Harry Potter and the Half-Blood Prince” will be the first Rowling adaptation since “Twilight,” but it also has girl power driving it. The series also has withstood date and seasonal switches and the audience has literally grown up with 16-year-old Harry, Ron and Hermione, leading to predictions for a big opening week.

If not record-breaking, certainly magical.