Web portal giant Google (GOOG) entrance into the online travel business is an eventuality with the 2010 acquisition of ITA Software.

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Generally a higher number of competitors means more choice for consumers, but in the fragmented online-travel business some consolidation is good news for buyers.

ECONOMIST: Business travel

Lashinsky likens his business to online travel booking sites like Expedia or Travelocity.

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Fueled by robust growth in its hotel booking business, online travel agency Expedia posted a 13% increase in gross bookings and a 14% increase in revenues last quarter.

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In a previous article, we discussed the partnerships between travel suppliers and online travel agencies as an evolving business model. (See How About a New Business Model for Priceline).

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FlyerTalk is an online forum for people who travel for business or pleasure, many of them mileage junkies, to share strategies to score tickets, upgrades, lounge access and other perks.

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The popularity of booking travel online has already driven many bricks-and-mortar travel agents out of business.

ECONOMIST: Face value

The company's own job listings, for instance, have allowed Google watchers and followers to spot advance signs of everything from its online office suite to a possible foray into the travel business.

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Sweeping economic reforms are opening up demand for business travel, notes Yoshihisa Yamada, an executive director at Rakuten, Japan's number one online travel firm and a 20% owner of Ctrip.

FORBES: Home, Sweet Home