I was on Facebook the other day and updated my status, it was nothing dramatic - just congratulations Ellie on the baby'. I could have just as easily updated this status on Twitter.
Around 4 hours later I logged into Facebook and to my amazement 9 people had liked my status. They didn't comment but were clearly happy that Ellie had had the baby and felt compelled 'to like'.
This got me to thinking - why is there not a 'like' button on Twitter. I know you can Retweet but some of the friends who liked my status have a different set of friends to me and so if they would have posted the news on their Facebook stream it would have meant nothing to anybody.
The amount of times I see good news on Twitter and think 'yeah that is cool' if I see it on Facebook I can like it and that person (however sad this may be) is pleased because they have brightened up someones day.
If Twitter introduced 'like' I would use it. Would you?
On Facebook, the importance of every post is dictated by how much interaction it generates. This is very visible: comments and Likes are listed on every post. In a hurry, you can decide a post's value by how many people have already interacted. Liking a post keeps the interaction within the OP's profile page. By scrolling through someone's profile, you get a feel for how popular they are within the service.
On the other hand, the value of a Tweet is proportional to the number of people who see it. This is sometimes difficult to guess when inspecting the original tweet, since Twitter does not track old-style Retweets. It doesn't matter though, since your message is broadcast to dozens (or hundreds, or thousands) of people you didn't reach by yourself. The threshold of quality is a little higher with a Retweet: in a sense, you must be willing to say the original Tweet yourself. But a popular Tweet can reach more people than a good Facebook post.