Starting today you can now use TripAdvisor reviews and even filter hotel listings by TripAdvisor ratings when you’re looking for a hotel on KAYAK. Given TripAdvisor’s unmatched content – more than 60 million user reviews and opinions from all over the world – we’re tremendously excited about this new relationship.

United States-based travel search site Kayak has bought Checkfelix, one of the leading travel search engines in Austria. Terms of the deal have not been disclosed, with Kayak also purchasing JaBo Software Vertrieb- und Entwicklung, which uses the Checkfelix as its trading name.

Our friends over at hotelmarketing.com are reporting that Kayak has opened up their logs to the rest of us to see how and what people are searching for and on. We can’t tell how recent this development is since Kayak doesn’t seem to blog anymore (last posting was back in May!) and they haven’t issued a press release since May either but we don’t remember seeing it before now.

Kayak.com has enhancedits Fare Alerts to make the tracking process easier forboth the flexible traveler and travelers with a specific itinerary in mind.