New Meta Keyword Tag “news_keywords” for news publishers to keep them happy?

Now, publishers can use this tag <Meta Name="news_keywords" content="keyword1, 2,3">to woo traffic from search engine. Even though Google Won't explictly support SEO methods, why they come-up with News keyword tag?

No business lunch is free my friend.  Let we explore the reason, why Google come-up with this
 
  1. To increase its revenue through Adwords display network – Google wants to keep the news publisher happy because they drive their revenue throulgh them. News publisher produce lot of fresh content. Most of the News Publishers are part of adsense network. News Publishers customers are google customers. For Google content matters…
     
  2. Videos - Most of the news publishers started uploading news vidoes & even telecast the news live through web. This Tag help to convey the video content better
     
  3. To Promote Site Search Product - Many News Publishers uses "Site Seach Product". This keyword tag may help the product to throw better result
     
  4. To Promote the Brand "Google News" 
If Google come-up with demographic Meta tag syntax, that will be of more help to "News Publishers" & "Google"