@Lightwave, interesting points on the user stats. Maybe you have to hover the mouse over their avatar to get the details. Edit: Ah, just noticed that you noticed!
Now for the narrowness of the opening screen...I actually prefer it! My understanding is that the research suggests that reading long sentences on one line reduces comprehension. It may explain why newspaper columns tend to be narrow.
One of the benefits of Xenforo is that the forum sections start higher up the page, or "above-the-fold" as they say. This helps the user experience, since you would see more forum sections or threads or content without having to scroll. i worked out I would get an extra 3 forum sections displayed on the index page, if we switched. Google theoretically prefers this too.