Kayak.com becomes the first meta-search site to search complex flight itineraries with beta testing of multi-city search. Also launching today are cabin class availability and enhanced features to Kayak Buzz.

Travelers who need to book trips with three or more city stops can now select the "Multi-city" option from the Kayak.com homepage. Users can also specify fare type, such as first, business and coach class. Kayak.com's powerful search engine will then find matching flights from hundreds of airline and travel sites, in one easy-to-use display. Consumers can customize the results for each leg of their flight using Kayak.com's signature filters to sort by stop, airline, price, time and airport.

"Millions of travelers already use Kayak.com to find cheap flights for one-way and roundtrip itineraries. But until now, no meta-search site has been able to search for a complex flight itinerary," said Steve Hafner, CEO and co-founder of Kayak.com. "About one-third of our user feedback requests multi-city search, so our engineers worked overtime to provide this functionality for the busy holiday travel season. We're delighted to help consumers find travel savings for even the most complicated itineraries."

Kayak Buzz, a new tool unveiled earlier this month that displays the lowest fares to the 25 most popular destinations from any airport or city, has been enhanced to target Buzz by region and theme. Based on customer feedback of the popular search feature, users can now personalize Buzz by region: World, US, Europe, Caribbean, South America, Asia, Africa and Australia/Oceania; and/or theme: ski, golf and gambling/casinos.

"If you just want to get away, Buzz provides a quick snapshot of travel ideas generated by hundreds of thousands of Kayak.com users," said Paul English, CTO and co-founder of Kayak.com. "It's also a fantastic tool for finding travel deals. Look for us to add more themes such as beaches in the coming weeks."

To get the Buzz, users input the departure airport or city in the Kayak Buzz section of the homepage and select the region and/or activity of interest. Within seconds, Kayak Buzz displays a list of 25 cities organized by popularity with an interactive map that displays all routes color-coded by price. The fares displayed are the lowest found by Kayak.com users over the previous three days.