Facebook has made two changes to its service recently that reflect the two directions it could go in: the ability to send status updates to the entire Facebook network, and the placing of the Event feature directly in the "What's On Your Mind?" box.
The first change, the ability to send your status updates to "Everyone" on Facebook, allows you to broadcast your updates to everyone on the Facebook network. It reflects the company's desire to be everything to everyone. It's a move clearly designed to target Twitter and co-opt their design into Facebook.
The second change, the placing of the Event feature directly in the Status Update box, makes it easier to send a quick event to your network/friends, such as getting together for a drink after work that night. It's a useful enhancement of Facebook's core features, and it makes the service more useful in communicating with your friends.
The status update change has gotten more press because it's an attack on a company that Facebook sees as a competitor. It's the wrong move. Facebook is a useful collection of tools to keep in touch with your friends and organize your social life around. It's become as big as it has because it streamlined the social networking concept. (Remember how you had to go through four different pages to post a comment to your friend's wall on MySpace? Not to mention all the bugs.) Twitter is a service best used for getting news and updates from and about important people and events. Sure, many people have their friends on Twitter but I know my friends' Tweets get lost in the deluge of other stories from the celebrities and news outlets I follow. On Facebook I can get, and want, just updates from my friends about their lives.
By trying to be all the hot things on the Internet at once and attack Twitter, Facebook is losing what made it popular. Allowing me to send my status updates to everyone on Facebook does not enhance my ability to stay in touch with my friends. As Mashable points out in the above article, this change will at best be wasted man hours in programming and at worst will erode Facebook users' confidence that the network is a place for them.