Perhaps the most significant loss is Knol, which was Google’s attempt to create a viable Wikipedia alternative. Although it managed to acquire over 100,000 articles, it never managed to compete, and will now be seeing itself out. Users can salvage information, however, by moving it to a new WordPress-based platform called Annotum. The Knol site will go inactive on May 1st 2012, and information on Knol will still be available for download or export to Annotum until October 1st, 2012.
Google Wave, which saw a halt to development in April of 2010, is finally going the way of the dinosaurs. As of January 2012 the site will become read-only, and everything will be deleted as of April 2012.
Also on the chopping block are Google Bookmarks Lists, Google Friend Connect, check out the full blog announcement. The Renewable Energy Cleaner than Coal project is to be given the halt, as well, but it likely won’t be missed since there was never a user-facing component to it., and Google Search Timeline, all of which will be discontinued within the next few months. For details on the end dates,
Coincidentally, Google Health – a service whose demise was announced earlier this year – recently sent an email reminder notifying users that it will be discontinued as of January 1st 2012, with data stored there remaining available for download until January 1st, 2013.