With Paris and her Simple Life continuing well past their allotted 15 minutes, and soaking up all that Internet bandwidth, from time to time, we need to return to Hilton Hotels (NYSE:HLT) to take a look at the commerce that spawned America's favorite, ditzy debutante.

Today, Hilton reported record first-quarter earnings of $0.16 per share, a 60% increase over the dime for last year, fueled by top-line growth from business travel and pricing power both there and in its leisure markets. The all-important revenue per available room (RevPAR) at comparable hotels increased 9.1% for the quarter, while overall revenue at owned hotels came in at a slimmer 3%. The biggest grower was -- once again -- the timeshare segment, which grew 23%

Reading through the Hilton earnings release, it's tough not to get a sense of deja vu. That's because the results from Marriott (NYSE:MAR) look so similar. And therein lies the problem with investing in the established hotel chains: You're more or less at the mercy of fickle travelers and the economy. When times are bad, everyone falls. And when times are good, the stocks make the uphill climb again.

That's also when the big players start adding capacity. Hilton plans to add about 140 hotels to the chain in 2005, amounting to some 18,000 rooms on top of the existing 363,000. With the pricing leverage possible at the luxury end, the firm has announced plans to enter Conrad Hotels in exotic destinations such as Tokyo, Dubai, and Indianapolis. (No, I'm not making that one up.)

Although the entire travel scene seems to be back, it's tough to be as enthusiastic about Hilton shares. Like peers Marriott and Starwood (NYSE:HOT), Hilton already trades above its usual historical ratios of price-to-earnings and price-to-sales. Unfortunately, when a stock is already priced at a premium -- especially these days -- anything less than continued perfection will give shareholders a bad night's sleep.

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At the time of publication, Seth Jayson had no positions in any firm mentioned. View his stock holdings and Fool profile here. Fool rules are here.