Micro-Social Network

I am using this very interesting app on Blackberry called Whatsapp. It is an instant messenger which does not require you to sign in. It just works based on your cell number (quite a smart idea in the first place). Me and my friends have formed a chat group on the service and have been using it for sending inane messages about nothing in particular. You can use it to broadcast your text, pictures, sound files etc to your friend group. I have already made 3 groups on this phone. And while using it today, I had a minor epiphany of sorts. I realized that I could use this little app to substitute Facebook. I have the facebook app on my phone too but it is very bulky and does not have an instant messenger like functionality. The chat interface is available on the laptop and not on the browser. But using whatsapp, I can chat with a select community of my friends, share files and all - and all this in an instant. For the stuff about me which I do not wish to broadcast or archive- whatsapp is actually quite better than facebook. Maybe facebook will do well to come up with a chat application