LAS VEGAS — George Maloof Jr. steps out into the hallway away from a raucous party where his luxurious Sky Villas have just been opened to the public.

The marble-encased villas' infinity pools jut out from the futuristic tower and offer a panoramic view of the Las Vegas Strip to the east. In one two-story villa, more than 100 guests are celebrating, among them Paris Hilton; actor Jeremy Piven; and Maloof's ex-girlfriend, Tishara Cousino, Playboy's May 1999 Playmate of the Month.

Maloof, whose family owns the Sacramento Kings, is plowing $650 million more into what will be a $915 million casino, resort and condo development known as the Palms.

The newest addition, the 40-story Fantasy Tower, includes the six Sky Villas, which span up to 10,000 square feet and can go for $40,000 a night. By September, the Palms' second tower will be topped by the first Playboy Club to be in operation in 25 years.

The wide-ranging expansion is a risk for the grandson of a Lebanese immigrant known for pushing the limits in a city that seemingly has none.

But Maloof, 41, is used to winning big. He parlayed an $8 million family investment in a neighborhood casino back in the mid-1990s into what is now a nearly $1 billion resort less than a mile from the Strip.

"As they say, 'All in,' " says Maloof, a late-night gambler in his college days at UNLV. "We're all in on this. We're all in."

By some accounts, Maloof is a visionary tycoon-in-training, following in the footsteps of billionaire Steve Wynn, who raised the level of opulence on the Strip with The Mirage back in 1989.

Maloof's main contribution to Las Vegas, though, has been to up the star wattage in what has increasingly become a celebrity playground: The Palms burst into the public eye when it hosted MTV's reality show "The Real World" in 2002, and later two seasons of Bravo's "Celebrity Poker Showdown."

Now, the sighting of celebrities and pro athletes is a cottage industry in Las Vegas, providing plenty of grist for gossip columnists, magazines and a permanent bureau for the entertainment TV show "Extra."

Maloof is credited with helping set the trend, especially with his courtship of the MTV generation.

" 'The Real World' was an absolutely staggering hit for all of those involved. ... That opened the floodgates for celebrities," says TV personality and AOL blogger Robin Leach. "So you've got to give George that."

Maloof also has been instrumental in helping Las Vegas inch closer to its dream of permanently hosting a professional sports franchise.

The city has long been shunned by leagues afraid of the taint of legalized sports betting.

But a little more than a year ago, Maloof received a call from his brothers who run the Kings — Joe and Gavin — with news the NBA was interested in bringing the All-Star game to Sin City. He called around to casino executives.

"I asked them if we had the opportunity to get the NBA in Las Vegas for the All-Star game, would you consider taking the game off the book?" Maloof recalls. "And everybody said, 'Absolutely.' "

After a call to the league commissioner and after an order was given from the state gaming commission not to accept bets for the event, the game was quickly OK'd.

Observers note that the influence of the Palms belies its size — by the end of September it still will have only 711 rooms, qualifying it for "boutique" status in a land of 3,000-room megaresorts, and its planned 599-unit condo tower won't be finished until around the end of 2007.

"It's not on the Strip, and it's not downtown, and it's not the biggest casino," says David Schwartz of the UNLV Gaming Studies Research Center. "What Maloof has been great at is using synergy — you know, things that are culturally very significant, things like MTV, things like the NBA. He's able to kind of tie that all together."