On Thursday this week, Facebook (s fb) is holding a press event focused on its mobile efforts. The “see our new Home on Android” tagline on the press invite is a not-so-subtle reference for what to expect, which should be two specific items: One focused on hardware and one on software. After months of Facebook phone rumors, some will focus on the actual hardware, but that’s not the big picture: Facebook’s software on other phones will have the larger impact.

The only way I can see being proved wrong on that is if Facebook reserves some must-have, “killer feature” for a Facebook-branded phone. The chances of that, however, are somewhere between slim and none.

Why? Because it really doesn’t benefit Facebook much to have a dedicated phone that offers a marginally better social networking experience; it won’t be enough to sell the phone. That’s why any phone unveiled at Thursday’s event…