Categorisation of online travel sites used to be easy. Either a site was transactional or non-transactional.
Either it made its money negotiating with suppliers for inventory and charging customer credit cards or it made its money from advertising and clicks through funnelling consumers from one place to the other.
In a post Meta-search vs Online Travel Agents: The Three Main Differences and Why They Matter, I mentioned that one of the major differences between an OTA (transaction site) and a meta-search site (non-transaction site) is that the transactional sites try to build up a unique product set – inventory (or inventory combinations) that no one else has – whereas the non-transactional meta-search company is focused on pointing to product that by definition is not unique as it is maintained by someone else.
Read the full story at:http://www.tnooz.com/2010/02/01/news/non-transactional-travel-sites-are-chasing-the-online-agents-on-unique-product-hunting-but-can-it-work/