The number on the card I have differs from what is listed here...here's the number I know works...
702-655-2277
http://www.centennialtransportation.com/
Spending a week in Vegas definitely means that at some point you'll be taking a cab somewhere at some point at least once. While we did take a cab a few times the Marriott set us up with Centennial Transportation for the same rate a cab would cost except we got a ride in a clean Lincoln.
Our driver, Ron, was an excellent host who gave us lost of advice, easy to talk to, and made us feel like high rollers. We ended up calling him 4 times for transport down to Fremont Street from the strip and it was 100x better than wrangling a taxi. Ron also took us around the back routes to show us some of Vegas's interesting lesser known places....much nicer than trying to fight through traffic on the Strip or on the freeway.
Clean cars, excellent drivers, simple flat rates easily comparable to taxi rates, and the last thing you'll be treated like is a simple fare.
Next time I'm in Vegas I'm definitely going to call Centennial for my transport needs.
From the Marriott Grande Chateau to Fremont Street our average taxi fare was $22-$24 before tip and Centennial charged $25...we tipped $5 for Centennial and $1-$2 for a cab. The few extra bucks we spent (mainly on the tips) were well worth the significantly more comfortable and safer rides.
Centennial Transport = A+