[film42]

The site says $99, however, upon clicking preorder, we see it costs $450 without a contract. AT&T of course says, "*Requires 2-yr contract with qualifying voice and data plans. Activation fee applies." So this cool little idea just got a whole lot more expensive.

I say wait for the rom to leak, and then dual boot it on a new Nexus 4.

UPDATE: Sorry, I misread, this is just an overlay. Still though, the point still stands.

[MojoJolo]

Based on what I read, the launcher is not available on Nexus 4. I don't get why Facebook Home doesn't support a stock Android.

[twism]

It isn't a rom. It's a launcher. You can download and install it from Google Play.