Yesterday I received this email from Yahoo!:

Dear User,

Unfortunately, the time has come to say goodbye to Yahoo! Groups Labs Applications (beta) and Groups Chat. We thank all the users that were a part of this program. We intend to use this learning to enhance Yahoo! Groups further with new features.

On July 04, 2012, we will shut down the Yahoo! Groups Labs  Applications (beta) and Groups Chat. We request you to backup any data that you might have created using the applications.

This closure will not affect your other services on Yahoo! Groups.
We look forward to continue having you as our customer.

Best,
The Yahoo! Groups Team

There's a real problem with Yahoo!'s attitude to user content. Content created by a user should never be deleted, and Yahoo! doesn't understand that. It's fine to shut down a service, but the content should remain in perpetuity, not be erased. It's valuable to the user, and until Yahoo! understand that, they won't be trusted by me.