User blog comment:Jenburton/Coming Soon: Message Wall in Labs/@comment-168424-20111027005046/@comment-954127-20111027081144

I'm more under the impression it was to make it easier to run for longer periods of time, time on site ads like the video ones. The Message wall doesn't require as many times to load as a talk pages, as a talk page you end up going to the editor and then back to the page after edit. Now with this, there is no more of that which means more time to show vid ads.