The first change up is how Google displays suggestions on a results page. If you've already performed a search for George Lucas, and perform a second search from the results page, Google tailors the first few suggestions based on the results that are currently being displayed. This is to help fine tune your search.
Next up is personalized suggestions. Google says that about 25% of all searches are repeats. Now, if you're signed into your Google account and have Web history enabled, Google will remember the searches you've perform and list them as you type.
The navigational suggestions are a tool that will help you get to a specific Web site sooner. If you start to type in a Web address, Google will show you the entire URL so you can go straight there.
Last up is sponsored links. If Google determines that the best result for your search is going to be an ad, it will show the ad and clearly mark it as a sponsored link.
So there you go.