Well, let's count them.
Currently under construction is the $2 billion Cosmopolitan with 3,000 rooms.
Also being built is the Palazzo at the Venetian; when completed, it will house 3,025 rooms at a cost of $1.8 billion.
Across Sands Avenue, Encore at Wynn Las Vegas is also going up, with 2,054 rooms at $1.7 billion.
MGM Mirage's Project City Center is the big one. In total, it will have 7,000 rooms and cost $7 billion.
So, within three years or so, Las Vegas will have an additional 15,000 hotel rooms at a cost of $12.5 billion. And that's just what's officially under way. Then you have to count announced hotel rooms.
Boyd Gaming's Echelon Place, which will replace the Stardust, will have 5,300 rooms at $4 billion.
Montreux, planned to replace the New Frontier, will have 2,750 rooms at $2 billion.
Fontainebleau, announced by Turnberry Associates for the old El Rancho site, would have 4,000 rooms at $1.5 billion.
W Hotel, announced by Starwood, would have 3,000 rooms at $1.7 billion.
Station Casinos has announced Durango Station and Aliante Station. Room counts and price tags haven't been revealed, but let's call it 500 rooms altogether at $1 billion for both.
Then there's the Southern Highlands planned for the far south Strip, with 600 rooms at $2 billion.
Nearby, M Resort could have 1,000 rooms at $1.8 billion.
The recently closed Klondike could be replaced with a Royal Palm Resort with 1,200 rooms at $1 billion.
The demolished Westward Ho site might be developed into a $1.8 billion resort with 1,600 condo-hotel rooms.
The men's magazine Maxim is partnered with a southern California developer who could open a $1.2 billion 2,300-room Maxim Resort next to Circus Circus.
Loews is planning a 400-room hotel across from MonteLago Village at Lake Las Vegas; no price has been announced, but let's call it a $500 million.
And in the highly speculative (read: doubtful) department, a group called Ultimate Sports Entertainment has announced a $4 billion 5,500-room "sports hotel-casino destination" in North Las Vegas near the Las Vegas Motor Speedway.
Altogether, the above add up to 43,140 new rooms at a cost of $35 billion.
And that doesn't include Harrah's metaresort, which is expected to be detailed in the next couple of months; rumored Elvis and Rolling Stone casinos; a flagship Station Casino to replace Wild Wild West; a new Cannery casino to replace Nevada Palace; a new megaresort to replace the Tropicana; a new megaresort for the Wet 'n Wild property; a Steve Wynn metaresort on the old Desert Inn golf course; and thousands of condominium and timeshare units in the Las Vegas resort corridor alone.