BlackBerry Messenger for Android shown in video
Fair warning to start, BlackBerry has already requested the original posting of this video to be pulled, so there is no guarantee that this video will last all that long. The video has a fairly solid walkthrough of BBM for Android, which looks a lot like how you'd expect. It comes complete with group chats, all the emoticons you might want, and even the familiar BBM notification bell.
Additionally, there is a cool option where you can add a contact through NFC if you have an NFC enabled device and you are running Android 4.0+ (the option requires Android Beam).