One of my favorite features that Microsoft acquired and added to Bing Search was Farecast. Farecast was a flight search engine that offered pricing predictions. I.e. should you buy now or wait for the price of the flight to go down. The search engine used historical flight prices to make a predicition.

Now Bing bought them and it is built into their travel search feature. It is now on the iPhone App. Here is a picture:

The other features include better maps:

Enhanced the backdrop so information on the map such as traffic details, business listings, pushpins, labels, etc. could popIncreased the font size corresponding to larger roads and added neighborhood labels so you can easily identify and convey locations in citiesAdded what’s Nearby with enhanced mapNow you can easily switch between the map view and the list view on the map

Forum discussion at WebmasterWorld.