If you go to Google's "Hot Searches" list, you'll find that the top three searches today were Apple, Robin Roberts, and the LA Kings. You'll also see how many times each has been Googled; for example, Apple had more than half a million searches in the past few hours.
All of these features are new with Google's revamp of its U.S. Hot Searches, which it rolled out today.
Similar to trending topics on Twitter, users can catch a glimpse at what is happening in national dialog or find breaking news. To figure out which topics users are gravitating toward, Google uses an algorithm that analyzes million of searches and then classifies them. Hot Searches is updated hourly.
Tamir outlines all of the new Hot Searches features here:
Unlike the previous version of Hot Searches, which always provided 20 daily results, the new page introduces a filtering system that helps us make sure that the list includes only the truly hottest news stories of the day. Also, when a few of the fastest rising search terms refer to the same news story, such as [tony awards 2012] and [audra mcdonald], they're now aggregated into one entry, which lists all the "Related searches" that go along with the main story. Lastly, the new list also provides an indication of how many searches have been conducted for each topic in the 24 hour period when it was trending.