I think integrated chat is good only for casual chatting. I mean say, if you want to tell your friend a website or some number etc. But for serious chatting, like I do with many of my classmate girls, it is insufficient.. :-D
I think let the chat be as it is and tell Facebook to build an app for us..
By the way, I'm surprised how Facebook can change their application to the likes of iOS 7 and can't even make an app for us. Also, where was their brand gone while redesigning for iOS 7, that they told MS to drop the Metro version of WP app?? Isn't it some kind of partiality??
MS is the biggest name in the tech world yet suffering so much. I think MS should tell others what it actually is.. Come on MS show them what you are..