A couple weeks ago, we talked about how Google Trends added top charts to the feature list.
What I did not mention and forgot about was the features Google Trends had prior that were removed quietly over time. Some of the "explore" features dropped out.
Why were they removed? Some speculate because Google wants to hide data.
Matt Cutts, Google's head of search spam, came in and said to make it less useful for spammers.
Let me quote Matt:
For a while, spammers were using data from Google Trends to find new phrases/topics to target for autogenerated spam. See this example.The new Google Trends UI is still useful for hot topics (Hey, Oracle just won the America's Cup!), but less useful for spammers.
So both less useful for users and spammers but more useful than it was after dropping those features.
Forum discussion at Hacker News.