Yahoo! has announced Yahoo! Groups will shut down from Oct 28.
Here’s what it has said:
Beginning October 28, you won’t be able to upload any more Content to the Site, and as of December 14 all previously posted Content on the Site will be permanently removed. You’ll have until that date to save anything you’ve uploaded.
The Yahoo Groups Site will continue to exist, however, all public groups will be made private or restricted. Any new group members will need to request an invite or be invited by an admin. Admins will still be able to manage various group settings, though some functionality will be limited.
Photos & files can be saved right from the Yahoo Groups Site, or you can download your data from the Privacy Dashboard.