a hotel booking engine integrated right in their own results for users, and then monetize the results page
Google is in that position now using a 3rd party technology to enable it. [tnooz.com...] . Direct deals with major chains may already be in place.
The result could be the same as any meta search engine, which ports out onto OTA's. But really i wonder why Google would even deal with OTA's or similar.
The OTA's would have to respond with fierce deals to pay for ever increasing PPC pricing, which would force chains to go direct to Google on their upcoming places technology in order to distribute initially at a lower rate on Google Places. Gradually Google can take more of the share.
For me it's a waiting game whilst Google repositions itself, before pulling the lever on the next strategic level when it's control becomes stronger.
Other verticals seem to be moving into this vortex. Basically any major vertical that has "comparison" technology as it's core value proposition is fair game - because Google can do it directly. Restaurants is one that i watch carefully from the supplier and web side. There must be countless others.