PORT CANAVERAL, Fla. - The first thing you see as you approach the Disney Magic, the theme park giant's much-ballyhooed (and much-delayed) entry into the cruise market, is a big statue of Goofy hanging over the rear of the ship.

He appears to be painting on the ship's name. But there's a larger message: Cruising is no longer just for grown-ups.

The red-white-and-black Disney ship (Mickey's colors), which had its inaugural voyage Thursday, is a $350 million bet that families will flock to cruising with the same gusto as, for example, seniors.

And Disney's not alone in its thinking. Nearly every major cruise line is beefing up children's activities and adding promotions to lure more families, the fastest-growing segment of the cruise business.

"Disney is saying it's going to revolutionize family cruising. But the truth is, the revolution has already begun," says Mike Driscoll, editor of industry newsletter Cruise Week.

Over the past five years, cruise lines have expanded children's playrooms and video arcades. They've added teen discos and kids-only pools. And they've begun stocking diapers and baby food in ship stores. At least one - Holland America - has begun kids-only shore excursions.

Behind the trend: baby boomers who waited to have kids and now want to take them along on vacation, as well as dual-income younger families.

"To ignore young families, with all their potential purchasing power, would be a dumb thing to do," says Bob Dickinson, president of Carnival Cruise Lines. Morbidly, he notes that the older cruisers who long have made up the bulk of passengers "do not have a lot of years of purchasing power left, to put it delicately."

Lower-priced Carnival, the world's largest line, probably will give Disney its biggest competition for families. It draws 200,000 children a year, nearly twice as many as two years ago (and more than any other line), and in February announced a deal with Universal Studios to offer combination cruise/theme park packages.

Fast facts on Disney Magic Size: 83,000 tons (third-largest in the world); 964 feet long; 106 feet wide Cabins: 875 Capacity: 1,750, double occupancy (2,400 maximum) Home port: Port Canaveral, Fla. Itinerary: Stops in Nassau and Castaway Cay (Disney's private island) in the Bahamas Speed: 21.5 knots, cruising (24 knots, maximum) Prices: Three-day cruises start at $799 per person, based on double occupancy and including airfare. Four-day cruises start at $909. Seven-day packages that include a cruise and three or four days at Disney World, including park tickets, start at $1,295. By Andrew Itkoff for USA TODAY

Disney, however, promises to take family cruising to another level. Instead of just a few playrooms for children, the Disney Magic has nearly an entire deck, with more than 250 activities. It also has the most extensive day care operation at sea. More than 50 counselors are available to watch children day and night.

"The idea," Disney Cruise Line president Art Rodney says, "is for parents to get a vacation, too."

It's a crucial point. Even Disney executives say the line's success could hinge on whether the experience is just as fun and relaxing for parents as for kids.

"The mistake other lines have made in the past (trying to do family cruises) was to just satisfy one segment of the market and not all," Rodney says.

Rodney, an industry veteran, is alluding to the demise of American Family Cruises, a line that was supposed to revolutionize cruising for kids but folded almost as soon as it started four years ago.

Disney, which planned to launch its ship in March, clearly had been banking on a strong summer to provide momentum for the rest of the year. But as a result of delays it blames on the shipyard, the company sets sail just a month before Labor Day, when most children head back to school and the industry's softest period, the fall hurricane season, begins.

Still, Rodney says sales are going well, although he won't give exact figures. He does say that about 40% of bookings are coming from adults without kids, passengers the line must have to succeed year-round.

Few industry executives doubt Disney will succeed. They see the arrival of Disney, the king of family vacations, as a watershed event in cruising. Walt Disney World, near Orlando, Fla., alone draws more vacationers each year than the entire cruise industry, and cruise executives say there's bound to be plenty of spillover. (More than half of the line's cruise bookings are from Disney regulars who have never been on a ship, says Judson Green, head of Disney's theme park division.)

"It's a tremendous opportunity for us as an industry," says Rick James, sales chief for rival Princess Cruises.

For its part, Princess recently added in-port baby-sitting and extended day care hours past midnight on all ships. It also lowered the minimum age to sail from 18 months to 12 months.

Even lines that use romance as their main selling point are taking notice. Windjammer Barefoot Cruises, for example, this year introduced the Junior Jammers, a summer program that allows kids to hunt for buried treasure on beaches and compete in the Wacky Olympics.

Still, most lines say they'll stop short of adding facilities as elaborate as Disney's. Too many tots could, executives fret, scare off what is still their core clientele: seniors, singles and married couples without kids.

"If you have too many families," Carnival's Dickinson says, "it starts working against the cruise experience."

Dickinson says Carnival curtails the number of kids by limiting the number of cabins that have a third or fourth berth (most parents won't pay to buy a separate cabin for their kids).

A few lines, such as upscale Windstar, have been steering clear of the family trend entirely. Windstar marketing chief Rick Meadows says the line's smaller ships appeal to people who want to get away from it all, including their children.

Still, of 37 cruise companies recently surveyed by Travel Agent, only a half-dozen didn't offer some sort of baby-sitting and kid activities. Even the Queen Elizabeth II, Cunard's white-gloved flagship, now offers two "family cruises" a year.

Says Holland America sales chief Jack Anderson: "We didn't set out to draw children. But we now find we have them on board year-round." Hence, Holland America's flagship, the 9-month-old Rotterdam VI, was the line's first launched with a dedicated children's area.

"We now have two responsibilities," Anderson says. "The first is to be sure children are not disruptive to the experience of our other guests. And secondly, to make it the very best vacation for kids. They're guests, too. If we do that, we're going to get them back."