You might think clicking "Like" is the only way to stamp that public Facebook affirmation on something — you're wrong. Facebook is checking your private messages and automatically liking things you talk about. Without asking you.
The scanning, which is either an oversight on Facebook's part of a deliberate effort — we're waiting to hear back from FB — increases the Like count for a given page just by you talking about it. Auto-scanning is nothing new: Gmail has done it since day one to serve us ads. But there are serious potential personal consequences here — what if I'm talking about something disgusting, loathsome, and offensive with a friend? Do I want Facebook to automatically chalk that up as a Like? No. And I doubt you do either.
The auto-liking could also be a big deal for those who want to artificially inflate their popularity online — say, people with something to sell. "Yeap, it won't drive any traffic to your website. But if your visiting an online store and you see a lot of likes under the product then this might cloud your judgement," notes one commenter on Hacker News, where the mechanism was first reported.
To test the auto-scanning, message this link to a friend — it should increase the like count by two. I was able to independently verify the same effect by messaging a link to singer The-Dream's official page to a friend. It increased his Like without me ever clicking the button. This isn't how it's supposed to work, Facebook. [Hacker News via Forbes]