The wall on all brand pages attracts almost all respondents' gazes. What you post matters. If you consistently create and publish great content -- items that really matter to your fans and add value to their day or contain an appropriate call-to-action -- you're more likely to attract and retain those readers.
Walls also attract the viewer's attention for the longest amount of time. Again, this reinforces the need for compelling content that builds on itself. Working in reverse chronological order (because that's how posts appear), Wall posts should compel the user to scroll down the page, keeping their focus and attention on your Wall. You should cross-reference previous status updates as a way to get visitors to scroll down the page and consume more of your content.
These are quite interesting findings on the use of the Facebook wall for pages that are active. One of my favorite pages, Magnolia Chicken Station from the Philippines on Facebook does this farely well. And I like looking at their recipes. A few celebrities are also doing this fairly well - I like Vin Diesel's page.
Thanks to Entrepreneur.Com for the idea and the photo below.