In the past, the page updates the news throughout the day, if you leave the page open. It seems, at least on some browsers, that Google News has stopped auto-refreshing with new news. This requires users to manually refresh the page.
Google News Guide 2 has confirmed the issue and explained they are working on a fix:
Anyone else experiencing similar issues, we've confirmed that there's a bug on our end that's preventing Google News from refreshing. We're working on a fix, and I'll get back to you as soon as there's an update.
Forum discussion at Google Groups.