As I explained at Search Engine Land, the search features include Location Filters (with drawing shapes, dates for your stay, price point filters and hotel ratings & user rating filters.
Of course, webmasters who run hotel sites are not too happy. If this catches on, you can bet these hotel listings will be listed above the competition in the future. I am sure Google will be very careful how they do it, but typically, Google properties rank above non-Google properties - see latest report on that.
Anyway, here are the features:
Here is a screen shot of the side bar:
Once you type in a location, you can then position the map with your clicker and draw lines around the specific location you want to stay. Google will then show you hotels in that area.
Clicking on the hotel icons on the map will show you more details about the hotel. You can then book the hotel or add it to your shortlist:
Booking a hotel is driven by Google Hotel Ads:
If you are unsure, just add it to your shortlist and you can compare the hotels on your list. Google also shows you if the price the hotel is currently offering is a good price based on the average prices the hotel charges throughout the year.