Interesting point from another Facebook Newsroom post. The News Feed is going to treat all Reactions as a show of interest. It'll try to show you more of the things that you react to. So if you click sad on everything, your News Feed will be sadder than a Nicholas Sparks story.
"Initially" i think is the point you're missing. This is like a trial run to see how people use it. Once they figure out the weighting I expect changes to the newsfeed.
Link for those interested: http://newsroom.fb.com/news/2016/02/news-feed-fyi-what-the-r...
Let me know if I've got it wrong because I'm making this point to everyone I see.