Not sure how to explain this, but I'll try:

On BF, when you're in a thread and get to the bottom of the page, the navigation dropdown menu is already set to the forum you're on with a "go" next to it. It makes it easy to get to the bottom of a page, click, and you're back to the thread list. Here, every time you click that menu, you're taken to the top.

It's not a big deal. I just like the way BF does it.