<<Google, which tried and failed to buy Twitter last year, is still studying its various features and building some of them into its own services. The next one it might borrow from Twitter is trending topics. Twitter exposes the keywords people are using the most or growing fastest at any given time under Trending Topics in the sidebar or in Twitter search.

Now some people are noticing similar trending topics in the left sidebar of Google News when they are logged in. Joe Hobot captured the screenshot at left on his blog. Some of the trending topics earlier today were “Greece” (which is considering an economic austerity plan) “Iran” (which is facing U.N. sanctions over its nuclear program), “Mobile Technology” and “smartphones” (no doubt due to the Mobile World Congress kicking off in Barcelona today). Google already shows the relative popularity of news topics in Google Trends, but showing them in Google News is probably more helpful.>>

http://techcrunch.com/2010/02/15/google-news-trending-topics