According to Industry sources, Facebook did a smart thing and approached top Android smartphone OEM Samsung about developing a Facebook Home powered model. Some might say that the Korean based tech titan did the smarter thing and turned Facebook down. But these sources say that some Android manufacturers haven't totally rejected the idea of putting together a Facebook Home supported model. Most likely these firms are waiting to see if Facebook improves the functionality of the launcher.
Meanwhile, OEMs like HTC, Sony and Huawei are said to be more interested in improving their own home screen and UI.