It is, but it doesn’t use any of the existing open source software, which makes it fun, different, and interesting. Heck, just having a non-blink/non-webkit/non-goanna/non-gecko browser is cool.
Their ports system (which they didn't invent, of course) offers a pretty nice compromise of continuing their "everything from scratch" ethos while letting people have fun porting. And who knows, maybe the ports will allow it to be a practical OS someday.
