It’s the preview version extracted from the HTC First ROM, anyway, it got some bugs such like the “Chat Heads” doesn’t work.
If you wanna give it a try, your device display resolution must up to 1280×768 (Nexus series phones are ok). And before you use it, current Facebook on your device must be uninstalled. The Facebook Home including 3 packages which should be downloaded respectively.
Click links below to download