"Is a" and "has a" are worlds apart.

I just dont think XMPP fulfills the uncontrolled and uncensored and surveillence resistent parts. We need to look at web of trust, bitmessage and such instead, those are more fun problems than "to spite facebook".

But sure, any solution will benefit greatly if its bundled with the browser since that appears to be the only program most users actually use on their computing devices. Imagine if Tor and a tor-relay or even tor-exit-node came preconfigured with every Firefox and turned on by default. That would be fun.

I'd rephrase it. Browser is turned into a virtual operating system for millions of people already. While it can be useful, I don't really like when that trend is pushed to the extreme and everyone rushes to run everything through the browser even without clear benefits. The point of that? I always prefer standalone chat clients (as well as e-mail clients and etc.). If some chat service can't interoperate with standalone clients, it's garbage.

Facebook can by the way, since they do use XMPP. Their problem is unwillingness to support federation. They are too selfish. So I never use their service (nor do I use their social network anyway).

Those are the majority, and if we want them to use Free and Open systems (which is my whole point here), then we have to create those systems in a way normal people will start switching from the closed systems and over to the open ones. And that is only going to happen if the open systems are easier to use and more accessible than the closed ones.

I am aware of the fact that Facebook uses XMPP (I mention it in the post). Still, extremely few people use it through a client. They use it through fb.com.

It's trickier than that. There are many open and federated XMPP services around, including those with web clients / interfaces available. Options are around. It's the sabotage of federation by "big" players which is a problem (or sabotage of interoperable protocols altogether).