Dennis Schaal

Suppliers, namely airlines, hotels, a cruise line and a car rental company, clearly dominate the top 15. Priceline and Amadeus are the only middlemen represented.

Bing has reorganized its search results pages to incorporate the social element, but it really has a long way to go before the service evolves into something really useful for travelers.

Expect Kayak to increase its leave of absence from the classic metasearch approach and to expand into new travel verticals with its Kayak booking path. Others, including Room 77, already are following Kayak's lead.

Start your engines. Kayak is beginning its road show in a bid to raise more than $100 million in an IPO. The company will face tough questions about Google's acquisition of ITA Software and whether it can paint a big enough growth story to satisfy would-be investors.

The new Wyndham Vacation Rentals site offers some modern, e-commerce pizazz. The rebranding to a more widely known brand makes sense, too.

Flipkey will continue to try to differntiate itself through reliable user reviews and inbound traffic from TripAdvisor, but it will need to overcome its parent company's propensity to under-invest in its non-TA properties.

Welcome to the big time, Virgin America. All this growth "don't come easy." Meanwhile, it looks like it is straightening things out with its Sabre reservations system and things should be on track before long.

Travel companies should fine-tune their cloud strategies after an Amazon Web Services outage took down Room 77, Pinterest, Instagram and Netflix. Given the cost-savings and efficiencies of cloud computing, travel companies won't be abandoning such services -- nor should they -- any time soon.

Can Portico by Exclusive Resorts and Inspirato resort to marketing super-exclusive vacation clubs to the mega wealthy? What Greek debt crisis? There probably is a market for this, and Steve Case and a bunch of other venture capitalists are making a downpayment on these clubs' viability.

What's behind the surge of users of TripAdvisor's Cities I've Visited app on Facebook? It didn't happen by chance.