It can be tough to get excited about anything that Facebook does in regards to Android, but this actually qualifies as big news. Facebook's Messenger app that has seemed somewhat redundant to many of us (since you can message from the regular old Facebook for Android application) has finally realized the dream that Facebook has apparently been working towards for quite some time. You no longer need a Facebook account to use Facebook Messenger. Why is this kind a of big deal? Good question.
Facebook Messenger has essentially become a new SMS app. Neither you nor the person on the other end need to have Facebook accounts in order to send pictures, message people using only their phone number, or create group conversations. Of course, you could already do most of that via any one of the plethora of SMS apps out there, but Facebook is one of the first well-known developers to make a move into the third party SMS space. I used Handcent for almost a year on my OG Droid until I switched to Google Voice, and some times I still miss Handcent's responsive, beautiful UI and ease of use.
I don't want to start a rant about Google Voice (Warning! Rant about Google Voice ahead!), but this is a service with a higher ratio of potential to missed opportunity than any other service I can think of. Google Voice is amazing, it gives you more control over your phone number than any other service, you can migrate it from carrier to carrier even if you are on a pre-paid plan, it's simple to point it to your desk phone and then back to your cell or visa versa, and to top it all off it features a great spam filter, which is increasingly necessary as spam texts become more popular. I would also be remiss if I didn't mention the ease with which you can read and respond to voice mails and texts through your browser using a Chrome or Firefox extension. But we are also talking about an app that has gone at least a year with no major feature updates. Group chats must be done through Google Talk, and neither of those services will allow you to send pictures. Not only that, but Google Voice doesn't even notify you if someone does attempt to send you a picture. You just don't get it and your friend has to go on living believing that you didn't think their picture of their food/child/poop was worth responding to. And why are Google+ messenger, Talk, and Google Voice all separate services that cannot interact with each other in any way? Why, Google, why?
These weaknesses and fragmentation among Google's messaging services are exactly why Facebook thinks it can get a toe-hold in the smart phone third-party SMS market. Time will tell, of course, but it will be interesting to see if Facebook can use its brand power to push us towards viewing Facebook Messenger as more than just a Facebook messenger.