The story about Google's AI Overviews passing off journalist Ben Black's prank about roundabouts in Cwmbran as fact until at least April 1 appears to be true. A Wales Online article corroborates this.
The original prank can be found here. This fake information was also submitted to Yahoo News, where it continues to exist despite Black publicizing that it was a prank.
Google's AI Overviews no longer shows information about Cwmbran and roundabouts. However, in May 2024, Liz Reid, the VP of Google Search, admitted that AI Overviews did present "odd, inaccurate or unhelpful" results in some cases. Reid stated that improvements have been made to detect satire and humor, but acknowledged that errors are bound to occur given the scale of queries submitted to Google.