Unless I'm mistaken, they did. Chat Heads is part of the most recent Facebook Messanger update. You can get it without Home.

and that's why I uninstalled Messenger. I don't want messages (which is facebook's version of email) drawing on top of my other apps.

Turn that feature off then?

Chat Heads is really great and it made me think apps multitasking could learn a thing from it. Say for example you double tap on the home button to get all open App Heads, close the ones you don't need anymore and open the others in mini windows by taping on their logos. I can see that being a much better experience than what we have right now (which is not multitasking at all).

It's been a while since webOS appeared and still noone has the easy of use it had for multitasking: http://www.youtube.com/watch?v=c20uhGxSxWo

Um. The only difference between webOS app switching and Android (ICS and beyond) recent apps is the size of the thumbnail...

Chat Heads is actually a separate feature although I haven't seen many people online note this. I cannot yet install Facebook Home on my device but when I last updated the Facebook Messenger app on my phone, I got Chat Heads.

They technically are two separate products. Chat Heads is a Facebook Messenger feature while Facebook Home is a separate app.

I currently have Chat Heads installed w/o any Facebook Home integration, as does everyone else I know using Chat Heads.

Great feature (terrible name).