A month ago, Google quietly released a new feature that shows article headlines within the search results snippet of major news sites. The first site to report this was Google Operating System. I do not believe Google ever officially announced the feature.
You can trigger it yourself by searching for [news] or popular news sites by name.
It comes up for these also:
But why not show up for popular blogs like ours?
I am not sure - it seems to currently only work for very popular news sites.
Tedster guesses it is based off "at least in part by how many times a navigational search shows up in Google News search."
Forum discussion at WebmasterWorld.