I don't know how many can replicate this but I searched for 'las vegas hotels' this morning and found Google placing what they call a "comparison ad" at the top of paid search listing, directing people to their recently launched Google hotel finder. You can even do a from price search in the ad.
This is an extremely aggressive move by Google. They will eat up the clicks share for these valuable keywords, drive more traffic to Hotel Finder and ultimately command higher rates that OTA's will have to pay to play. If this strategy works, Kayak is in big trouble. I see the exact same thing happening for Flight searches.
Google does no evil, right?