There are fan sites, and then there are fan sites. The One Ring has been around long enough that they have earned their spot atop the mountain as the end-all be-all source for news on all things involving the cinematic interpretations of the work of J.R.R. Tolkien.
When they call a source reliable, they've been doing this long enough to know what that means, and they wouldn't publish a random rumor unless they were fairly sure there is truth to it. So let's use that as a jumping-off point and just take it as a given that when The One Ring says that New Line is considering a title change for the final chapter of "The Hobbit," there's something to it.
The original plan for bringing "The Hobbit" to the screen was to break it into two parts. The first would be called "An Unexpected Journey," and the second would be "There And Back Again." When they made the decision to break the story into three parts, they named the second film "The Desolation Of Smaug" and left "There And Back Again" as the final title. There was a moment where they registered a possible alternative title, "The Battle Of Five Armies," but that seemed like something they considered without ever committing to it.