Small stars have been placed to the left of story headlines.
You will need to be logged in to your Google account for this new functionality to work or clicking on a star will take you directly to the log-in page.
Essentially, 'starring' a story block in Google News lets Google know that you're interested in this story, and when there are significant updates, the story headlines will be in bold .... and they will also be placed in a new 'starred' folder for later viewing.
The result is automatic and immediate :
Google (as always) wants your feedback. There's a link for your thoughts in the new blog post on this feature from Google News here.